es
ALKYLA TlON
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R. NORRIS SHREVE
PURDUE UNIVERSITY, LAFAYETTE, IND.
A"
I S previous reviews, these alkylation references are classified by the method of bonding, whether to oxygen, nitrogen, carbon, sulfur, silicon, or metal. In 1949, there is again a great increase in the carbon-carbon alkylation references, owing to the technical importance of alkylation reactions having this bonding. The most important alkylating agents are olefins with an acidic type of catalyst such as hydrogen fluoride, sulfuric acid, aluminum chloride, or boron trifluoride. Other common alkylab ing agents are alcohols, alkyl halides, and ethers. Grignard reagents are also employed; these are presented at end of carboncarbon miscellaneous alkylations. The only two articles on the economics of alkylation that were found were by Sutherland and Doegey (S&,244), who discuss this important aspect of alkylation and polymerization. Side reactions. especially polymerization of an olefin, very frequently accompany alkylations and should be reduced in order to lower costs. Goldsby and Watson (83)claim that polymerization, side reactions, and high conversions of olefins may be minimized if the hydrocarbon feed is passed through a permeable wall reaction tube. Bergniann ( 1 4 ) studied alkylation reactions using aluminurn chloride and hydrochloric acid as catalysts. He found that isomerizations are intermolecular reactions always involvkig carbonium ions Branched-chain paraffins secm first to form tertiary chloi id(!&\\ 11ic.hadd to olefin\.
OXYGEN ALKYLATION Perron and Paquot (177, 178) describe the preparation of symmetric ethers derived from long-chain aliphatic alcohols, using p-toluenesulfonic acid as a catalyst. In the preparation of dihexadecyl ether, the intermediate was shown to be hexadecyl-p toluenesulfonate. Practical information for obtaining maximum yields of the isomeric methyl ethers of glycerol is given by Aloisi and Bonetti (3). Moureu et al. (169) allowed ethylene oxide to react with aqueous ethylene glycol in the presence of sulfuric acid to prepare diethylene glycol. Knunyants et al. (1%) found that hydrogen fluoride reacts with ethylene oxide under a variety of cwnditions to give chains of polyethylene glycols, with minute content of polyethylene fluorohydrin. They successfully introduced the hydrogen fluoride in ethyl ether as a solvent. Petrov (179)investigated the effect of the acid-base nature of the catalyst on the order of addition of alcohols to divinyl oxide. In the presence of alcoholates, erythrol ethers which were secondary alcohols were obtained, while with boron trifluoride the isomeric primary alcohols were obtained. A patent by Schmerling (204)describes the preparation of alkyl norcamphanyl ethers by heating a Zhalobicycloheptane and an alrohol at a temperature of from 100' to 300' C. A patent by McGrew ( 1 4 7 ) describes the production of ethers of trimethylolmelamine in an anhydrous medium. Dry hydrogen chloride is bubbled through trimethylomelamine in absolute ethyl alcohol at 5" C., and the solution is then neutralized with sodium ethylate bdow 20' C. to give 2,4,6-tris (ethoxymethyl) triazine. In a French patent (223)the Soci6t6 franqaise Duco gives a method for preparing the higher alkyl ethers of dimethylolurea. The lower alkyl ethers of dimethylolurea are heated with the higher alcohols and a solvent such as benzene. Sodium phthalate or phthalic anhydride may be used aa a catalyst. The Williamson synthesis is particularly applicable to making niixed ethers. Baker (10) used this method to prepare benzyl
phrnethyl ether from benzyl chloride and sodium 2-phenyleth oside. In addition to the expected product, the residue waa found to contain 2,3-diphenyI-l-propanol. Similarly, Rieveschl (199) has patented a method for preparing dialkylaminoalkyl benzhydry1 ethers and their salts by refluxing benzhydryl bromide and MeCH(OH)CH2NMez. The upper layer is filtered and treated with oxalic acid dihydrate in isopropyl alcohol to give 2-dimethylaminoisopropylbenzhydryl ether acid oxalate. Newton (16.2) has patented a method for producing dialkylaminoalkyl benzhydryl ethers by reaction of a benzhydryl halide with an :tlkali metal alcoholate of a dialkylaminoalkanol. Thompson with General Aniline & Film Company (263)has patented a process for obtaining vinyl methoxymethoxyethyl ether by treating iUeOCH20CH2CH,0H containing potassium hydroxide with hydrocyanic acid dimer. The ether may then be polymerized in chloroform with boron trifluoride. The preparation of ethers of oximino acids and acid chlorides by ethylation with ethyl sulfate and sodium hydroxide in aqueous acetone is patented by Hartung (96). In a Swiss patent (76), Geigy describes a series of ethers of the type a-cyclopentyl benzyl-2-diethylaminoethyl ether which are of therapeutic value. They are made by variations of two methods: (1) condensing a-cyclopentylphenylcarbinol with EtpNCH2CHzCl and sodium amide in benzene, and (2) condensing a-cyclopentylbenzyl chloride with EkNCHgCHlONa in benzene. Gerber and Crutin (78) investigated the reaction of diazomethane with phenols in the presenve of propanol. Contrary to the previous work of Schonberg and Mustafa, they found that when stilbestrol is treated with diazomethane in propyl alcohol-ether, there is no evidence of the formation of any dipropyl ether. Palazzo (170)discusses an interesting aspect of the behavior of diazomethane. Diazomethane is not decomposed by water, but when exposed t o sunlight, it dissociates and the free :CH2 methylates the water. In the direct alkylation of the phenolic group in alkaloids, simultaneoue alkylation of the hydroxyl group and the nitrogen group is obtained. To prevent this, Folkers and Koniuszy (60) have patented a process whereby the alkaloid is transformed t o the amine oxide by hydrogen peroxide, alkylated with dialkyl sulfate, and reduced with zinc in acid solution. Rosenwald (198) has patented a process for oxygen alkylation of phenols using a carboxylic acid catalyst such as trichloroacetic acid, trinitrobenzoic acid, or oxalic acid. In a discussion of substitution in 3,4dialkylphenols, Parkes ( 1 7 1 ) gives a preparation for the methyl ethers using methyl sulfate. In an article discussing the stereochemistry of substituted cholesterol derivatives, Henbest and Jones (100)state that p-7-bromocholesteryl acetate reacts readily with alcohols to give the corresponding @-7-alkoxycholesteryl acetates. Zeiss (989) has patented a process for methylating methyl-6-hydroxydehydroabietate with methyl sulfate in an aqueous solution of an alkali metal hydroxide. According to Haworth and co-workers (981, tetrahydropurpurogallin in dioxane, treated with ethereal cyanamide, gives the dimethyl ether. When treated with 20% excess cyanamide, the tetrahydropurpurogallin gave the trimethyl ether, which in 65% potsium hydroxide with methyl sulfate gave the tetramethyl ether. Rajagopalan et al. (183) have worked out syntheses for some of the important partial methyl ethers of flavonols involving partial benzylation, methylation with methyl sulf%te,and debenzylation. Bell (18) discusses methylation of polysaccharides and separation of the methylated cleavage products in this summary of
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I N D U S T R I A L A N D E N G I N E E R I N G CHEMISTRY
carbohydrate chemistry over the past five years. Lolkema (14 $) has patented a process for etherifying starch. Anderson and coworkers ( 4 ) have investigated the methylation of yeast nucleic acid to obtain an understanding of the mode of linkage of the carbohydrate radicals of polynucleotides. Houston (107) describes the use of ethers of p-hydroxydiphenylamine as identification derivatives of alkyl halides. The methylation of guar polysaccharide has been carried out by Swanson (946). Timell (256) has investigated the methylation of native cellulose with methyl sulfate and alkali. Five different ethers were obtained. Although the various groups have different reactivity, all hydroxyl groups seem to be accessible to the alkylating agent. Timell (867)has also studied the mcthylation of regenerated cellulose with methyl sulfate and alkali. The preparation of cellulosc ethers containing substituents with branched chains has not been successful,presumably because the branched-chain substituents are too hulky to penetrate the crystal lattice of the cellulose. Timell (%56)suggests dispersing the cellulose in a quaternary ammonium Lase, thus destroying the crystal lattice. The alkalinity of such dispersions is sufficient to permit alkylation. The ethylation of coellulose in the form of low viwosity cotton linters with ethyl sulfate has been investigated by Cyrot (39) with regard to influence of sodium hydroxide, soaking concentration, pressure, and temperature of ethylation, concentration of ethyl sulfate, and effect of catalysts. Chedin and Tribot (31 ) studied the ethylation of cellulose under vacuum and found that for each temperature from 60' to 100' C. there exists a value for the vacuum necessary to give a very sharp maximum degree of ethylation. Berger (13) reported that a quantitative treatment of montmorillonite in ethereal solution gave consider:Me methylation. Common silica gel was also easy to methylate. Orth (169) ha.a attempted to determine the hydrogen ions that fis the (hydrogen plus aluminum) value in bleaching earth by riicthylation with diazomethane.
NITROGEN ALKYLATION
I British patent (996)describes the preparation of monoeryl tertiary amines of the type N-ailyl-N-(2-dimethylaminoethy1> aniline by treatment of N-(2-dimethylaminoethyl)-aniline with nlly1 bromide. The catalysts recommended are sodium iodide, copper powder, or copper chloride. The Wellcome Foundation with Goodson and co-workers (980) has patented a process whereby polymethylene dibromides are treated with primary aiiiines to obtain the N,N-dialkyl or diaralkyl polymethylenediamines. Benzene, ethyl alcohol, or xylene was generally used as a solvent for the reaction. Rawlings (184) has patented the pro.duction of N-alkyldiaminodiphenyl sulfones (4-amino-4'-propylmiinodiphenyl sulfone) from the corresponding diamine and alkyl bromide as therapeutic agents against microorganisms. Compounds of the general formula PhCH4(CHz).NRR', where R is an aliphatic radical with at least 2 carbon atoms, R ' is hydrogen or an alkyl radical, and n is 1, 2, 3, or 4, are described in a Dutch patent by Goldschmidt (84). They are stimulators of respiration and can be obtained from the corresponding NHz compound or by synthesis from the corresponding halide and HNRR'. In mother patent Geigy (73) describes the preparation of pure P ~ ( ~ M ~ O - C ~ H ~ C H Z > N CHCI ~ Hby ~ "treating ~ Z . pMeOCiH4CHaNHPh with Me2NC2H4CI.HCI. The success of the process depends upon the complete hydrolysis of the original salt at a pH .of 6, whereas the salt of the product is stable. Grimmel and E'reyermuth (88) have patented a process for the preparation of N-alkylated indole with aqueous potaasium hydroxide and a dialkyl sulfate in the presence of toluene. The methylation of BUN(CHMeCONHMe) (CHMeCONHMer) with sodium amide and methyl sulfate to obtain BuN(CHMe CONMe& is described in a patent by Geigy (77). According to a patent by Gresham (88), N-alkyldialkanolaminea free from .u\vgen alkylated derivatives are obtained by treating a dialka-
1651
nolamine, and alkali metal or alkaline earth metalcarbonate, and an alkyl sulfate a t 20' to 150' C. for 1to 4 hours. Optically active N-methyltyrosine has been prepared (97)by methylating natural tyrosine with methyl sulfate. The phenolic hydroxyl group is not affected by methyl sulfate. Similar methods have been used to prepare N-methyltyrosine betaine in higher yields. In apatent by Danforth (40) aralkyl alkyl amines are prepared by the condensation of a vinyl aromatic hydrocarbon with B primary or secondary amine in the presence of alkali metal or alkali metal amine. Phenethyldibutylamine is prepared from styrene, dibutylamine, and sodium. A British patent (49) describes the addition of ammonia and amines to olefins under pressure with an alkaline catalyst to give amines. Another British patent (921) describes the methylation of N-alkyl-N-arylalkylene diamines with cyanamide to give ditertiary alkylenediamines which possess interesting therapeutic properties. In Japanese patents (221, 919) Sobe and Ito describe the addition of one or more salts of copper, manganese, iron, cobalt, nickel or calcium to the dehydrating substance used in the preparation of alkylated aromatic amines from aniline and aliphatic alcohols. A French patent (64)deals with catalysts for use in the ethy1:ttion of aniline. Alumina supported on silica or carbon was prepared by making alkali metal aluminates slightly acid to litmus or treating the aluminum salt with ammonium hydroxide. Brown and Eldred (9.9)have made a study of the reaction of triethylamine with ethyl iodide and of quinuclidine with methyl iodide, ethyl iodide, and isopropyl iodide. Quinuclidine reacts considerably faster than triethylamine with each of the alkyl halides. The rates show a marked decrease from methyl iodide to ethyl iodide to isopropyl iodide and the energies of activation show a corresponding increase. Shih0 (809) reports a new method for alkylation of amines, in which PhCOEt is treated with HCOnEt to give PhCEt(OEt)e which, when heated, yields PhC(0Et):CHMe. This was heated with amines and the condensation products were reduced catalytically with platinum black or with active aluminum in a mixture of alcohol and ether to give PhCH(NHR)Et. Harvey and Caplan (96) have obtained a patent for a process for producing tertiary alkyl substituted amides which are useful in compounding rubber and as accelerators in wlcanimtion. They are made by treating a tertiary alkyl alcohol, preferably of 4 to 6 carbon atoms, in the presence of mineral acid condensing agents, with an amide such as oxamide, acetamide, or benzylamide. A patent by Gresham and Grigsby (87) describes the preparation of these N-tertalkyl amides from nitriles by treatment with a tertiary alcohol, a tertiary olefin, or an ester of a tertiary alcohol in the presence of an acid catalyst. A British patent (994) has been issued involving the aralkylation of sulfonamides free from basic amino groups to give products useful in the textile industry as wetting and dispersing agents. A thorough discussion of the reductive alkylation of amines using hydrogen as the reducing agent appears in Organic Reactim (63). A British patent (999)has been issued dealing with the condensation of dimethylamine and aldehydes of the type PhNRCH&HO in the presence of a reducing agent to give ditertiary diamines. According to a patent iasued to Sharplee Chemicals, Inc. (907),better yields can be obtained in the reductive amination of aldehydes and ketones if the oxo compound is added slowly, thus avoidiing such side reactions as aldol condensations, and the addition of ammonia and primary amines to double bonds. I n another British patent (206) the secondary amines which are useful for synthesis of flavins are prepared in one step by hydrogenating a solution of an aldonic acid lactone and a primary aromatic amine at about 130 atmospheres in the presence of a platinum catalyst. A Russian patent (24)describes the methyl sulfate methylation of methylxanthine to methylcaffeine. Cook and Moss (36)have patented a procesa for the reaction of appropriate tertiary amines with alkyl halides, dialkyl sulfates, eto., to produce quaternary ammonium compounds of the type
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INDUSTRIAL AND ENGINEERING CHEMISTRY
Vol. 42, No. 9
ItCONH(CH2)aK’H&2HaX. A J a p a ~ e spatent r ($68)involves the fluoride catalyst. The process can be either a batch or conpreparation of quaternary amines of high germicidal action. They tinuous operation. .Johnson and Rope (181) used the reaction product of a fluophosphoric acid and boron trifluoride as a catalyqt are made by reaction of tertiary amine having at least one fatty to alkylate isohydrocarbons with olefins. Fifty per cent convetacid radical with ClCH&HzOPh or a halobenzyl derivative. sion of ethylene was obtained by Paushkin and Topchiev (174) i t 1 Rieveschl (190) reacted an alkyl halide with derivatives of alkylating isopentane, using boron trifluoride aa a catalyst. Ph2CHOCH2CHzNHzto form quaternary ammonium halides. Hadden (89) patented a process for alkylating low boiling isoIn another patent, Moss and Cook (168) describe the synthesis of paraffins and olefins in a fractionating-type column, using a liquid (stearoylaminopropy1)-dimethylbenzyl ammonium chloride by reacting the product of (stearoylaminopropy1)-dimethylamine hydrogen fluoride catalyst. A patent by Frey (6.4)describes :i and acetaldehyde with PhCH2CI. Watanabe (677) treated distillation process for hydrogen fluoride recovery. Hydrogel) fluoride and an alkali metal fluoride or ammonium fluoride art. tertiary amines of the type PvleC~HIOCH2CHzNRz with aliphatic used to alkylate and isomerize isoparaffins and nonparaffinic. halides having 8 to 18 carbon atoms to obtain new quaternary alkylatable hydrocarbons in a process patented by Passino (172). ammonium compounds. Useful pharmaceuticals (curariform A continuous or batch isomerization and alkylation using 12 to 40 agents) of the type (RC~H~)(R~C~H~)-CHOCH&HZNR*R~weight 70boron trifluoride of a hydrogen fluoride catalyst ha5 (CHR4C02R6)Xare prepared from haloacetic acid eaters and 2been patented by Clarke (32). Readrig and Vinyard (185)have aminoethyl benzhydryl ether, according to a patent by Rieveschl patented a process for the recovery of hydrogen fluoride from the (193). Shelton and Van Campen (808) prepared substituted product of alkylation of isoparaffins. An excess of olefins is pyridium and piperidium germicidal compounds from alkyl or added to the overhead from fractionation before depropanizatioxi. dialkyl pyridine or piperidine and an alkyl halide. Livshits et al. The hydrogen fluoride forms alkyl fluorides, which are less vola(14 discuss ) the synthesis of quaternary derivatives of hydrocotile than the propane and are returned to the cycle after deprotarnine. Rieveschl(191) has also patented a process for obtaining panization. In the alkylation of low boiling isoparafhs in the quaternary ammonium derivatives of powerful antihistaminic and presence of hydrogen fluoride, an azeotropic solution containing antispasmodic properties by reaction of Zdialkylaminoethyl 35 to 45% hydrogen fluoride can be recovered. Alexander (8)has benzhydryl ethers with dialkyl sulfates or alkylaryl sulfonates in patented a process for the concentration of this solution b\ an inert anhydrous solvent. In a Japanese patent (110)p crystallization. dodecylphenetidine is alkylated with alkyl sulfates to give germiIverson (180) has also patented a process for the recovery of cidal preparations. A Swiss patent (‘74) describes the nitrogen hydrogen fluoride catalyst from an alkylation process. The with methylation of l(~~-hendecyl-4rnethylbenzyl)-piperidine catalyst is introduced into the top of a fractionating column, methyl sulfate to give a quaternary compound. According to where it meets hydrocarbon vapors hot enough to decompose the another Swiss patent (76) methylated stearoylcyanoguanidine, fluorine compounds and vaporize the hydrogen fluoride from thv obtained from the reaction of stearoylcyanidine with methyl catalyst. The hydrogen fluoride vapors are taken overhead, sulfate, can be supermethylated to give a waxy mass which is where they are condensed and separated from the hydrocarbon especially suitable for softening cellulose fibers. Steensholt (636) discuaes the optical specificity in methylation processes. When which is refluxed to the tower. In another patent (863,890), ii similar column treatment is used to decompose the organic. methylating ethanolamine or Me2CH&Hz0H to choline, Dfluorine compounds, but the stripping zone is filled with aluminuni methionone is a much more efficient methyl donor than the G turnings. When using fluorinecontaining catalysts, small form. Geigy (78) has patented a quaternary compound which amounts of organic fluorides are formed which are removed from renders fabrics water-repellant and safe to laundering. It is obthe product by adsorption on a number of solid porous contact tained when 2( octadecyloxymethy1)-4chlorophenol is condensed materials, commercial grades of which contain substantial with formaldehyde and the resulting condensate is treated with amounts of silica which forms silicon tetrafluoride, which reacts pyridine. with water to form ortho- and metasilicic acid and silica. The CARBON-CARBON PETROLEUM ALKYLATIONS latter compounds tend to plug the pipes and equipment. Waddill (878) has patent,ed a process for preventing these siliceous deFLUORIDES posits by removing water from the hydrocarbon stream until Hydrocarbons of high sulfur content form complexes with it is less than 35% saturated. Wildman (186)describes how the hydrogen fluoride catalyst, reducing the occurrence of alkyl silicon tetrafluoride can be removed by washing the alkylate with fluorides and tar formation in hydrogen fluoride alkylation, acan equal volume of aqueous sodium hydroxide. Organic fluorides cording to a patent of Skinner’s (116). Kelley (186) claims that a such as ethyl fluoride, which forms an azeotrope with propane, propane-propylene mixture added to a distillation column of the can be removed by forming complexes with boron trifiuoride ac. effluents from a hydrogen fluoride alkylation unit reacts with discording to a patent by Linn (141). In another patent (1.60)Linn solved hydrogen fluoride, effecting its removal, and introduces describes how small amounts of organic fluorine compounds are propylene to the alkylation system, permitting the hydrogen removed from hydrocarbons by means of liquid hydrogen fluoride fluoride distillation column to be omitted. Kanhofer ( 114) and sludge from a previous treatment of hydrocarbons with patented a process in which the dissolved hydrogen fluoride and hydrogen fluoride. organic fluoridea are dehydrofluorinated by passing through a Topchiev and Paushkin (859, 860) studied various boron zone containing an appropriate catalyst such as aluminum rings. fluoride compounds as catalysts in alkylation and polymerizatioii The hydrogen fluoride can then be removed by distillation. reactions. Paushkin (178)has made some interesting observations Frey (63) patented a process in which a 1 to 1 hydrocarbonon the physicochemical nature and catalytic activity of boron trihydrogen fluoride mixture is the alkylation catalyst, butanes and fluoride compounds. The catalytic activity of boron trifluoride in butenes being passed through this mixture and alkylated. alkylation and polymerizatioa reactions increases with the Trimethylpentanes of increased octane ratings are produced by acidity of the compound. The catalytic properties of boron the alkylation of isobutane with isobutene, 2-butene, and 1fluoride in the condensation of cyclohexene and epichlorohydrin butene according to a patent by Dart, Kuhn, Penick, and Wagner with phenols have been studied by Levas (139). (41). All three isomers have to be present or the quality of the product is adversely affected. Matuszak (1.49)alkylated monoALUMINUM CHLORIDE cyclic aromatic hydrocarbons and furan with a low boiling olefin Several alkylations producing high-quality antiknock gasoline using hydrogen fluoride as a catalyst. Vermillion (86’9)alkylated were reported using aluminum chloride as the catalyst. .4 isobutane and ethylene using a hydrogen fluoride-boron tri-
September 19%
I N D U S T R I A L A N D E N G I N E E R I N G CHEMISTRY
catalyst composed of an aluminum chloride-hydrocarbon complex saturated with aluminum chloride produced alkylate of high antiknock quality with isoparaffins and olefins, according to the Standard Oil Development Company (930). The Texaco Development Corporation (960) alkylated isobutane with ethylene in a 3 to 1 molar ratio using aluminum chloride and not more than 0.1% hydrochloric acid by weight of hydrocarbon aa a catalyst. The Standard Oil Development Company (231) alkylated mixed olefins with isobutane using an aluminum chloride-hydrocarbon complex catalyst. Hill (103) patented a procesa for reaction of isoparaffis and olefins with an aluminum chloride-hydrocarbon complex catalyst, the hydrocarbon containing a branched-chain hydrocarbon. Skelton (216) alkylated ethylene with isobutane using an aluminum chloridealumina catalyst, producing principally 2,s rlimethylbutane. Usines de Melle (966)patented a process for producing synthetic lubricants by polyethylating benzene with ethylene below 1 10' C. and with aluminum chloride as a catalyst. The alkylate waa mixed with dichloroethane and refluxed for 2 hours. Dupm (46)haa patented a process for producing synthetic lubricants by alkylating bensene with dichloroethane in the presence of aluminum chloride, and then further alkylating with a chlorinated oil having a 22 to 24% chlorine content. Heinrich (99) patented a method for making a synthetic lubricating oil by alkylating a polymer of an a-olefin with an isoparaffin in the presence of aluminum chloride. Lebedev (138)haa studied the mechanisms of the catalytic action of aluminum chloride. Korshak and Lebedev (139) have investigated the structure of complex compounds of aluminum halides with alkyl halides by the w e of ultraviolet absorption spectra. A supported aluminum chloride catalyst suitable for alkylations has been patented by Rupp and Harding (900). T t is prepared by dehydrating bauxite to 3% water with a heated paraffinic hydrocarbon and depositing aluminum chloride carried by the hydrocarbon into the bauxite. The effect of hydrogen on the action of aluminum chloride on alkanes haa been studied by Tpatieff and Schmerling (118). They found that when pentane waa heated iAith pure aluminum chloride at high hydrogen pressure, no reaction took place, whereaa, under nitrogen pressure, autodestructive alkylation of the pentane to butanes, hexanes, and higher alkanes took place. Schmerling (901)found that solutions of anhydrous aluminum chloride in the lower nitroparaffins, unlike the solutions in alcohols, ethers, and ketones, are catalysts for alkylation reactions. The solutions are miscible with aromatic hydrocarbons, thus making homogeneous liquid alkylations possible. Hepp (101) has patented a process for controlling the viscosity in alkylation processes by use of aluminum chloride. In another patent by Hepp (log), recovery of aluminum halide is effected by subjecting the aluminum halidehydrocarbon complex to destructive distillation while paesing preheated gaseous paraffis over it. The paraffins pick up the freed aluminurn chloride and pass to the conversion zone as a source of hydrocarbon feed and fortification aluminum chloride. According to a patent by Miller (I&$), aluminum halidehydrocarbon complex catalyst can be made relat,ively noncorrosive by bringing the catalyst into contact with finely divided free alkali earth metal. A patent by Dornte and Young (43)describes the use of a catalyst comprising a complex addition compound of a Friedel-Crafts metal halide and an ether, especially a chlorinated ether. It can be used as an alkylation catalyst in the production of high antiknoek hydrocarbons. SULFURIC ACID
In this section the alkylation catalysts discussed are sulfuric :icid unless specific modifications are described. Van Steenis and Waterman (967) found that a reaction time of 2 minutes was sufficient for the good alkylation of isopentene with isopentane if there was intimate mixing, the catalyst waa emulsified with an
equal amount of hydrocarbon before the reaction, and there wm a 500% excess of isopentane. Middleton (168, 163) patented a method for mixing the catalyst with a small portion of the reaction mixture and feeding it to the reaction, and also patented a process to use in the apparatus. N. V. de Bataafsche Petroleum Maatschappij (166)claims that the activity of t6e catalyst will be lengthened if the isobutane, the olefins, or both feed streams are first treated with a strong hydrocarbon-insoluble carboxylic acid. Goldsby (83)alkylated butene with isobutane in an apparatus described in his patent. Wolk (987)produced higher boiling isoparaffiic hydrocarbons by alkylating olefins with isoparaffins. The product was in the gasoline boiling range. Jones (199) emulsified isoparaffinsand olefins with sulfuric acid by subjecting them to a 2000- to 5 W p o u n d shearing pressure by means of a homogenizer valve in a process for alkylating isoparaffins with olefins, The Standard Oil Development Company (839) prevented the freezing of the catalyst in making an aviation safety fuel by using as the catalyst a 0.1 to 0.5 mole per mole of sulfuric acid mixture of sulfuric acid and ethylene, ethyl sulfate, or dimethyl ether. Voorhies and Sydnor (970)depressed the flash point of a catalyst solution with a small amount of an alkyl sulfate, the alkyl group being methyl, ethyl, or propyl, in slkylating hydrocarbons that are normally gaaeous. The flash point was originally -7' C. and waa lowered to -18' C., which waa the temperature a t which the alkylation was carried out. The Anglo-Iranian Oil Company, Limited (61,attributes the acid catalyst consumption of the alkylation of pentenes to pentadienes, which are removed by treating the total butane-free distillate with sulfuric acid, neutralizing, and separating by distillation. N. V. de Bataafsche Petroleum Maatschappij (163) makes 3,bdiisopropyl salicyclic acid by propylating salicyclic acid at 60' to 70' C. The iinc and calcium salts of this acid impart good anti-ring-sticking properties to lubricating oils when used in 1% concentrations. MIXELLANEOUS PETROLEUM ALKYLATIONS
Thacker (961)alkylated olefins with parttfiic hydrocarbons with three to seven carbon atoms at elevated temperature and 500 pounds per square inch pressure, using 0.1 to 5% by weight of the charge of bromine and a compound such as carbon tetrachloride or bromide, chloroform, or bromoform, 0.4 to 9% of the charge. Stover (841) produced triptane using propylene dibromide m a catalyst in alkylating isobutane with cyclopropane. The temperature waa 850' I?. and the pressure 4500 pounds per ' alkylate, of which square inch. The yield was 41.5 volume % 11% waa triptane. Stover (940) also alkylated isobutane with propylene using water as a catalyst obtaining a yield of 47% alkylate. Bloch and Schaad (16) dehydrogenated and isomerized butane in one step, and alkylated the mixture with isobutane to produce antiknock quality fuels. This method has the advantage of not having to separate unconverted butane from hhe olefins formed in the dehydrogenation and isomerization. Isagulyants (119) reviews the three known methods of making triptane. There are nine references in the review. The methods mentioned are methylation of olefins with a methyl halide and hydrogenation of the product, demethylation of iso-octane, and alkylation of propylene with isobutane. McAllister, Anderson, and Peterson (I&) patented a process for making normal a-oleiins of four to five carbon atoms from ethylene and propylene, isomerizing the a-olefins to &olefins, and alkylating these with isoparaffins to produce motor fuel components. Stevens (938) claims that the quality of the alkylate is improved by recycling enough isobutane emulsified with the alkylation catalyst to keep the isobutane-butene ratio about 1774, where the reactants first contact the catalyst. Harper (99)claims that the octane number of the alkylate is increased if isopentane is selectively removed from the feed stock before the feed is alkylated.
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INDUSTRIAL AND ENGINEERING CHEMISTRY
Matuszak (149) patented a four-step process for producing motor fuel alkylate. In the first step an olefin is alkylated with an isoparafi. An excess of a cyclic alkylatable compound is added in the second step and alkylated with the by-products of the first step. In the third step an olefin is added to alkylate the excess of cyclic Compound. The fourth step involves the separation of the product, He claims this process counteracts the formation of undesirable by-products of the usual alkylation reaction. N. V. de Bataafsche Petroleum Maatschappij (168) patented a process for fractionating the feed mixture to an alkylation unit to remove normal alkanes which decrease the antiknock properties. A 46.8 volume yo yield of alkylate was obtained by Stover (9.41)by the reaction of isobutane and propylene, using water as an alkylation catalyst. The Universal Oil Products Company (86.4) patented a process which increases the molecular weight of an aliphatic halide by the weight of an olefin that is condensed with the halide-for example, tertbutyl chloride and ethylene yielded primarily 3,3-dimethylbutyl chloride, Lovell, Mulligan, and Lichtenwalner (1.46) reacted an alkyl halide with an olefin and obtained an olefin of higher molecular weight-for example, tetramethylethylene and methyl chloride yielded triptene. Carter (30)patented a process for reaction of a primary aliphatic monohydric alcohol containing 3 to 15% of an alkali metal alcoholate with a primary alcohol or a secondary alcohol containing a methyl and hydroxy group on the same carbon atom to yield higher saturated alcohols with small amounts of unsaturated alcohols. Gasson and co-workers (69) have patented a catalyst produced by the interaction of ethylene on alkali metal alcoholates dissolved in polyether solvents. This catalyst can be used to effect improvement in the vinylation of alcohols by ethylene. A catalytic hydrogel suitable for use in cracking, reforming, isomerization, polymerization, and alkylation reactions has been patented by Hunter and Kimberlin (111). The preparation of a promoted ferrous oxide catalyst suitable for synthesis of hydrocarbons is described in another patent (933). It is easily fluidired and has a long effective life. Corson and Brady (36) discuss the preparation of another catalyst by heating phosphoric acid to 140" F. on a copper tray with magnetite and traces of aluminum, titanium, calcium, and magnesium oxides, After addition of the iron is complete, the temperature is raised, Celite is added, and the mixture is heated at 300" to 400' F. for 16 hours.
CARBON-CARBON AROMATIC ALKYLATIONS Francis (61) discusses the effect of solvent extraction of early reaction products in the catalyst layer in the alkylation of aromatic hydrocarbons in theliquid phase. He claims that alkylation is extremely rapid, but that in obtaining good contact between the reactants and catalysts delays are inherent. Steegmuller (834) claims that aluminum chloride alkylation of benzene by an alkyl halide does not take place by the aluminum chloride forming an addition compound with benzene with the evolution of hydrorhloric acid, and subsequently reacting with the alkyl halide. Aluminum chloride instead forms a complex with benzene, which reacts with the alkyl halide, forming the alkylate and hydrochloric acid, and releasing the aluminum chloride. Illari (216) discusses a study of the reaction of benzyl alcohol with aluminum chloride to see if any benzyl chloride was formed. The purpose was to see if benzyl chloride was an intermediate in the benzylation of benzene, in order to help explain the mech:inism of condensing alcohols with benzene using aluminum chloride as a catalyst. It was concluded that benzyl chloride is probably not an intermediate. Fahim and Mustafa (66) made a comparative study of the Wurtz-Fittig and the Clemmensen methods for preparing several aromatic hydrocarbons, The Clemmensen method generally gave better yields. Schmwling (903) methylated aromatic hydrocarbons at ele-
Vol. 42, No. 9
vated temperatures in a continuous process with methanol, methyl ether, methyl halide, and similar compounds. The catalyst was an acid of phosphorus and a siliceous material that \\ill undergo compound formation with the acid. Given and Hammick (81) discuss gas-phase, alumina&lica catalyzed methylation of benzene and its methyl homologs, using methyl ether as the methylating agent. Of the twelve possible isomers, prntamethylbenzene was the only one that probably was not formed. The yields decreased as the number of methyl groups in the ring increased. Peter Spence and Sons, Ltd., Chall, Crundall, and Cullinane (898) patented a process for making 2methylnaphthalene with naphthalene, methyl ether, and an alumina-silica catalyst. Armstrong, Grove, Hammick, and Thompson (7) discuss some catalyzed gas phase methylations of naphthalene with methyl ether, using bauxite as the catalyst. Cullinane, Chard, and Meatyard (38)ethylated benzene with ethyl alcohol using an alumina-silica catalyst. The reactions were conducted in the gas phase a t 350' C. for the most satisfactory yields, although the conditions were varied to determine their effect. The Universal Oil Products Company (266: patented a process for alkylating benzene and other mononuclear aromatic hydrocarbons with ethylene and other oleiins or alk? 1 halides. The catalyst is an aluminum chloride-hydrocarbon complex formed by treating aluminum chloride in the presence of an alkyl halide or hydrogen with the olefin. The catalyst is 60 to 80 weight % aluminum chloride. Francis and Schlesmaii (68) patented a process for producing a yield of i'oyOethylbenzerir with some hexaethylbenzene and other isomers formed during the reaction. The catalyst is aluminum chloride and the ethyl at in^ agent is ethylene. Topchiev, Paushkiu, and Sergaeva (961 wrote a Russian article on the phosphoric acid-boron trifluoritit. alkylation of benzene with ethylene and propylene. Short and Olmstead (912) have patented a process for making compounds such as cumene from benzene and a mixture of au olefin such as propylene and its alkane. A compound such a4 nitrobenzene having a higher boiling point than the aromihtic. hydrocarbon, miscible with it, and in which the ole& has a larger solubility than thk aromatic hydrocarbon, is added to the alkylation feed. N.V. de Bataafsche Petroleum Maatschappij (166) patented a process in which cumene is made by treating benzene with a cracked gas product of propano and propene selectively absorbing propene and then alkylating. Paushkin and Topchiev (176)alkylatedbenzene with propylene at room temperaturesusing a phosphoric acid-boron trifluoride catalyst to obtain high yields of cumene. Thomas and Haensel (968) used hydrogels of silica. alumina, or thorium oxide to catalyze the alkylation of benzene with olefins such as propylene. Natuszak (148) patented the alkylation of benzene, for example, using propylene and hydrogen fluoride to which propane was added. Serijan, Hipsher, and Gibbons (206) prepared o-, m-,and p butyltoluenes. The para and meta isomers were made from tertbutyl alcohol and toluene, but the ortho isomer was prepared in 18% yields with the o-methylbenzene magnesium bromide and tert-butyl chloride. Tsukervanik and Poletaev (969) studied tlie alkylation of benzene and toluene with primary butyl and isoamyl alcohols. Tatarenko and Tsukervanik (848) alkylated 1,2,3,4-tetrahydronaphthalenewith amyl alcohols using aluminum chloride, zinc chloride, and phosphoric acid as catalysts. With zinc chloride they obtained an 30% yield of %amy1-1,2,3,+ tetrahydronaphthalene. N.V. de Bataafsche Petroleum Maatschappij (167) patented it process in which aromatic hydrocarbons are alkylated with isoparaffins. Alkenes and polymers form oxygen compounds which poison the catalyst, so these are removed and their formation i. prevented by excluding light and air from the reaction, or adding inhibitors such as hydroquinone. Stevens and the Phillips Petroleum Company (237) patented a process of reacting benzene and an olefin of not more than six carbon atoms in presence of silica and not more than 10% of an
September 19%
INDUSTRIAL AND ENGINEERING CHEMISTRY
oxide of a metal of Group I11 B or IV A. The Compagnie frantpise de rafhage (84) patented a process for alkylating an aromatic hydrocarbon by partially converting an ole& to an alkyl halide and then alkylating the benzene. Birch, Habeshaw, and Lowry (16) patented a process for alkylating benzene in a mixture of benzene, cyclohexane, and methylcyclopentane with an aluminum chloride-hydrochloric acid activated catalyst. The alkylation reaction is more rapid than isomerization of cyclohexane. Bailey, Pickering, and Smith (9)made butyl-, amyl-, and hexylnaphthalene by reaction of 1-bromonaphthalene with the alkyl bromide by a Wirtz-Fittig reaction. N.V. de Bataafsche Petroleum Maatschappij (164)reacted a mixture of iso- and nalkenes with a strong polybasic acid, separated the two alkenes, and. alkylated an isoparafh with the normal alkene and an aromatic hydrocarbon with the isoalkene. Garach (68) made some alkyl benzenes to extend the range of optical analytical methods. Amyl-, hexyl-, heptyl-, octyl-, monyland cyclohexylbenzenes were made from the alkyl halide and benzene by the Friedel-Crafts catalyst. Axe (8)patented a process for making alkenyl aromatic hydrocarbons from 1,3-diolefins and a phosphoric acid-boron trifluoride catalyst. Hunt et a2. (109,110) patented two processes for making alkylsubstituted aromatic sulfonates for detergents and wetting agents. They made 2-gtolyldodecane from toluene and 1-dodecene in the presence of copper or nickel and hydrogen fluoride. 2-(p Ethylpheny1)-dodecane was prepared from bromodecane and pethylacetophenone through the Grignard reaction. The alkylated benzeneswere then sulfonated to produce the sulfonates. Hart and Simons (94) studied the kinetics and mechanism of the uncatalyzed alkylation of phenol with alkyl chloride. The) report that the reaction is of the &st order with respect to the alkyl chloride. They propose that the reaction involves the amphoteric-medium effect in which bonds are made and broken simultaneously; phenol is a highly associated liquid capable of proton transfer. Plank and Socolofsky (180) alkylated phenols using hard, friable gels of drying oils as catalysts. They claim that they are efficient catalysts, unaffected by moisture, and not requiring extensive regeneration. Winkler and Mortimer (886) used an activated alumina catalyst such as activated bauxite to alkylate phenols with aliphatic alcohols or ethers. Hart (93)made o-tertbutylphenol by alkylating 4bromophenol with isobutyl alcohol and then removing the bromine atom. Basterfield and Imperial Chemical Industries, Ltd.(11) butylated phenol with sulfuric acid as catalyst, raised the temperature to isomerize, and removed the solid ptertbutylphenol. The liquid residue waa then recycled. Rosenwald (197) reduced the yield of di-tertbutylphenols by using hexane to extract the monoalkyl phenol aa rapidly as it was formed. Stillson and Sawyer (939)prepared 2,B.di-tertbutylphenol, useful aa an antioxidant in petroleum producta, by alkylating a phalophenol with isobutene, and then removing the halogen from the alkylated phenol. Kitchen (189)patented a process for alkylating phenols. Reiff and Hartough (187) condensed phenols with polyalkylbenzyl bhlorides to obtain polyalkylbenzylphenols. Monroe (166)alkylated resorcinol with alkyl chloride to obtain diallylresorcinol. The Socony-Vacuum Oil Company (997)patented tl process for alkylating a phenol with an alkyl halide and then reacting the product with phosphorus pentasulfide to obtain an alkyl-substituted dithiophosphoric acid ester. Carpenter and Easter (89) passed isobutene into an agitated 4-methoxytoluene and sulfuric acid mixture to yield 3-fer& butyl4methoxytoluene. They similarly made 2,4di-tert5methoxytoluene. LavrovskiI, Mikhnovskaya, and Olen’chenko (137) obtained pbutylaniline by alkylating aniline with butene. Side r&ctions produced the N-alkylate. Cracking, cyclizations, and destructive alkylation also occurred. Hass, Berry, end Bender (97)added sodium and ethyl alcohol to nitropropane and reacted thst mixture with pChNCdI&H&l to give a M.S%
1655
yield of l-(p-nitrophenyl)-2-nitrobutane. Various modifications were tried. Thompson (864) condensed arylalkanes in the presence of tetraethyllead to form polymylalkanes. Zaugg (988) reacted 2-hydroxy-l,4naphthoquinone (lawsone) with C;H,CH = CHAc in pyridine, adding the CH(C,H&€12Ac group in the 3 position. This product may be cyclized. Wheatley, Cheney, and Blinkley (981)added sodium hydride to pethoxyphenol and treated this with benzyl chloride to obtain a 42% yield of 4ethoxy-2-benzylphenol. Whitman (888)alkylated an aromatic or hydroaromatic hydrocarbon having a carbon atom with at least two hydrogen atoms that is attached to the nucleus through a single bond; the nuclear carbon atom is attached to another nuclear carbon atom with a double bond. A mono-olefin is used aa the alkylating agent. Ward, Blenkinsop, and Company, Ltd., and Pritchard (I%?) reacted 2-naphthalene sulfonic acid with acetaldehyde and obtained methyl-bis-(sulfonaphthy1)-methane. Kolbel (131) reports a synthesis of lubricating oil through the condensation of chlorinated Fischer-Tropsch hydrocarbons with naphthalene. The Monsanto Chemical Company (167) prepared 2,5-dichloroethylbenzene by either chlorinating ethylbenzene or ethylating pdichlorobenzene with ethylene using aluminum chloride aa the catalyst. The activity of aluminum chloride as a catalyst is moderated and its solubility in hydrocarbons is decreased with boric acid to prolong the catalyst life and make the recovery of the catalyst easier, in a patent by Mavity (160). Warburton ( 8 W ) patented a method for purifying a F’riedelCrafta catalyst mixture by passing it over a bed of coprecipitated alumina-silica particles. A method for making the alkylation products of an aromatic alkylated phosphoric acid mixture, noncorrosive haa been patented by D’Ouville (4).The Standard Oil Development Company (899) methylated aromatic hydrocarbons with methyl alcohols or compounds such aa dimethyl ether, which yield methanol under the reaction conditions, using as the catalyst an oxy acid of phosphorus such aa phosphoric acid and a siliceous carrier material such as kieselguhr. The Lion Oil Company (149)alkylated an aromatic hydrocarbon with a mono-olefin of six or more carbon atoms, using an artificial hydrous aluminum silicate as a catalyst. Wadsworth and Lee (974) alkylated naphthalenes with olefins, using aa the catalyst anhydrous toluene sulfonic acid in 3 mole % concentration.
CARBON-CARBON MISCELLANEOUS ALKYLATIONS Caesar and Sachanen (87) alkylated thiophene with olefins. The catalyst waa an activated natural clay or an adsorbent of silica and oxides of amphoteric metals. The type of product waa controlled by the ratio of reactants. Kuta and Corson (133) alkylated thiophene with an alumina-silica or phosphoric acid catalyst because the usual Friedel-Crafts catalysts were unsatisfactory. The products consisted of about 60% monoalkylthiophenes and the rest higher boiling polyalkylated thiophenes, polymers of thiophene, or polythienyl. Caesar (86) claims that in contrast to the statement of Kutz and Corson, thiophene can be alkylated by Friedel-Crafts catalysts without excessive resinification of thiophene or decomposition if suitable conditions are used. Hansford and Caesar (80)used boron trifluoride to alkylate thiophene or its derivatives. Bredereck, Haas, and Martini (18)methylated nucleosideswith dimethyl sulfates at various pH. It was found that the pH had a great influence on where the methylation occurred in the nucleoside. Mouaseron and Manon (160)discuss the action of diazomethane on cyclohexanone to form cycloheptanone. Steinegger and Reichstein (886) discuss lunarine. They methylated a sample of this crystalline alkaloid. Schmerling (808) treated cyclohexyl cbloride with ethylene and aluminum chloride to obtain 1-(20hloroethyl>l-ethylcyclohexane.
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INDUSTRIAL AND ENGINEERING CHEMISTRY
Vol. 42, No. 9
Tallman and Stuart (247) claim that alkyl-l,3-dihydroxyments in a peroxide alkylation process. An example of this phenylpropanes with alkyl groups of five carbons or less at 1,2,process is to treat P-hydroxy-l,4naphthoquinonein acetic acid 1,2-,1,3-, or 1,2,3- positions have estrogenic activity. They and slowly add diacyl peroxide; 3-alkyl derivatives are obtained reacted ethylmagnesium bromide with p,p-dimethoxychalcone to as the product. Tatevosyan and Tuteryan (249) made various obtain pMeOCrH4COCH~CH(CLH6)CJ140Me-p. E. I. du chloro-unsaturated alkyl derivatives of malonic acid-e.g., 3Pont de Nemours & Company (48)patented a process for making chloro-2-butenylmalonic acid. The product probably is very long-cthain carboxylic acids from ethylene and a shorter cartoxic. lmuylic acid having a t least one a-hydrogen atom. Catalysts GRIGNARD REAGENT for this reaction are compounds which can yield free radicals. Thc temperature is in the range from 50' to 400' C. and superEverett and Kon ( 6 5 )discuss a method for making l-pheny1-2atmospheric pressures are used. naphthyl and 1,Z-dinaphthylethylenes. Benzylmagnesium chloGawron (71) used the chloromethylation conditions of Vavon, ride reacts with 1-naphthaldehyde to give 1-phenyl-2-naphthylRolle, and Calin (268)to react veratrole, acetic acid, and dichloroethylene. Fuson, Gaertner, and Chadwick (67) prepared some methyl ether to yield P(chloromethy1)veratrole. Fusco and methoxyaronitriles and reacted them with Grignard reagents such Caggianelli (65) treated anisole with hydrochloric acid and as ethylmagnesium bromide to form the corresponding methoxyformaldehyde to give an unreliable yield of methoxybenzyl phenyl ethyl ketimines. Fuson and Chadwick (66)reacted ethylchloride. magnesium bromide with 2-methoxy-l-naphthonitrile,obtaining Gavallini and Ravenna (70) refluxed CGHF,C~HICH~CO~H l-propionyl-2-methoxyaphthalene, 2-methoxynaphthalene, and with Cl(CH&N( CzHs), and obtained 2-diethylaminoethyl-42-naphthol. Campbell, Helbing, and Florkowski (28) reacted biphenylacetate. The Societe des usines chimiques RhBnecompounds like C6I&H=NR' and RMgX to obtain amines of Poulenc (320)patented a process for reacting ClCHzCHzN(CH3)2 the type CJLCHRNHR'. DuVigneaud, Stacy, and Todd (61) to give therapeutically active substituted ethylenediamines. synthesized diethyl (1-ethylpropy1)malonate by treating ethyl Watson and Burton (278) have patented a process which they ~. and magnesium bromide with CzH&H: C(C O ~ C Z H ~ )Kinney claim reduced the reaction time of alkylation to 2 to 3 minutes Spliethoff (128)reacted polyhaloparaffins with Grignard reagents. and increased the yield of primary alkylation products. Ross, For example, butylmagnesium chloride and carbon tetrachloride McAllister, and Anderson (199) obtained a patent for a catalytic gave a 16.5% yield of l,l,l-trichloropentane. alkylation process. Mizuch (166)studied the reactions of methyl-, ethyl-, and Coffman et al. (33) synthesized tetrafluorocyclobutane by propylmagnesium halides and organomagnesium compounds of reaction of tetrafluoroethane with ethylene in an evacuated reprimary and secondary amines with the acetic and benzoic actor at 150' C. Oxygen must be excluded from the reaction or esters of 9-(hydroxycarbazole). Wieland (284) added ethyl the reaction proceeds explosively. Homologs of ethylene may be oxalate to sec-butylmagnesium chloride to synthesize methylused instead of ethylene itself. ethyl pyruvic acid. Hsing and Li (108) reacted alkylmagnesium Bruson and Raterink (34) added methyl acrylate to a solution bromide and ethyl ethylenetetracarboxylateto give 71% tetraof 2-acetylcyclopentanone and tertbutyl alcohol, made the soluethyl l-alkyl-1,1,2,2-ethanetetracarboxylate. Dedusenko (&) tion basic with a quaternary base, let it stand for 1.75 hours, synthesized butylisopropylacetylene by adding ethylmagnesium acidified it, and distilled the 2-(2-carbomethoxyethyl)-2-acetylbromide to isopropylacetylene, refluxing, then adding (C4H,0)t cyclopentanone under reduced pressure. Several similar comSO,. The Societe pour I'industrie chimique B Bdle (826)patented pounds were prepared in this manner. a process for making diphenyl(3-alkylaminopropy1)carbinol by The Shionogi Drug Manufacturing Company (211) patented reaction of the appropriate Grignard reagent with CeHsCOCsHs. a process for making alkyldecahydroquinoline by simultaneously hydrogenating and alkylating quinoline with a saturated primary SULFUR ALKYLATION alcohol. In a manner analogous to oxygen, sulfur can also be alkylated. Kutz, Nickels, McGovern, and Corson (184)describe a pressure For example, Eby (62) has patented a process for preparing alkylation apparatus for alkylating indan with ethane, using a thio ethers by treating alkyl halides with mercaptans in the 25% alumina-75% silica catalyst to give a 75% yield of the presence of Friedel-Crafts type catalysts. Me3CCH2CHMeCHt monoethyl derivative. Other alkylating agents were used and SAm and MeaCSAm have been prepared from AmSH and the mentioned in the article. corresponding alcohols, using stannic chloride, aluminum chloride, Buchta and Dauner (26)refluxed diethyl phenylethyl malonate or boron trifluoride as a catalyst. These compounds are useful with sodium, then added cyclopentyl bromide, and refluxed as solvents, plasticizers, corrosion inhibitors, etc. A description 7 hours to give diethyl cyclopentyl phenylethyl malonate in 75% of the preparation of some thio ethers by means of an alcoholate yields. catalyst is given by Goldsworthy and co-workers (86). A Dutta and Sengupta (50) Synthesized Dbmethionine by reFrench patent (116) discusses the sulfur alkylation of thiaction of chloroethyl methyl thio ether with sodium acetoacetic ammeline by means of agents such aa dimethyl sulfate in alkaline ester, and treating with ammonia to obtain the amino acid. medium. The product of 4acetamidophenyl propyl sulfone Hoffman-LaRoche (104) has a patent for synthesizing 2-methylthrough the treatment of 4AcNHC&3O2Na with propyl 3-carbethoxy-4phenoxymethyl-5-cyano-3,4dihydro-t3( 5H) pyriiodide in alcohol has been described (6). In a British patent done by methylation. Snyder and Eliel (217) treated ethyl(47)E. I. du Pont de Nemours & Company treats with preparasodium malonate with 1 methylgramine to give a 22% yield tion of thio ethers from ethylene and sulfhydryl compounds such of (1-methyl-3-indolylmethyl) malonic acid. Wibaut and Vromen as hydrogen sulfide, methanethiol, or ethanethiol at high pres(883) successfully prepared several 3-methyl-4alkyLpyridines sures, Szabo and Stilles (246) also discuss the reaction of mercap from Smethylpyridine and an alkyl acid anhydride and zinc. tans with unsaturated compounds to obtain thio ethers. The British Resin Products, Ltd., Evans, and ThurstonSILICON ALKYLATION Hookway (19)patented a process for the cyanoethylation of 1,3,5trimethylene trisulfone. These products are resin intermediates. There is a widespread interest in the preparation of alkyl Pearson (176) studied the ethylation of diethyl malonate by silicon compounds. According to Hurd (114) when silicon is resistance measurementa. Renfrow and Walker (188) alkylated treated with an alkyl or aryl halide, better yields of the alkyl silanes are obtained with shorter reaction times. Gilliam and ethyl acetoacetate by the tert-butyl alcohol method, and cleaved hfeals (80)passed alkyl or aryl halides over finely divided siliconto produce ketones. Fieser et n2. (61) reported extensive experi-
-
September 1950
INDUSTRIAL A N D ENGINEERING CHEMISTRY
copper alloy of definite particle size under conditions such that a maximum yield of &Six* was obtained, and the production of RSiXs and other by-products was minimized. Infiesta and Achdn (117) dmcuss the fact that methyl chloride and silicon react only slightly at 350' C. forming highly chlorinated methyl siloxanes, but if 5 to 28% copper is present as a catalyst, the reaction begins at 250' C., and at 300' C. the principal product is MaSiHCI. An apparatus for preparation of alkyl silanes by this method haa been patented by Sellers and Davis (806). A tube equipped with a helical ribbon conveyer moves the silicon-cab alyst mixture up through the tube, keeping it near the inner side of the tube. Optimum temperature is maintained by removing the heat of reaction. In another patent (79) Gilliam claims 67% conversion of silicon to Me2SiCla when methyl ohloride was passed over a mixture of silicon and copper (as copper, cuprous oxide, cupric oxide, or cupric chloride) and small amounts of zinc at elevated temperatures. When carbon tetrachloride was passed over silicon, cuprous oxide, and zinc chloride the conversion was 66.6%. The Dow Chemical Company has been issued a British patent (46) for the production of low molecular weight alkylsilicon halides in up to 40% yields by passing a mixture of hydrogen halide and alkyl halide or olefin vapors over a silicon or silicon alloy bed heated to 250" to 550' C. Another British patent (81) describes the preparation of alkenylchlorosilanesby treating vinyl or allyl chloride in the vapor state with silicon in the presence of copper. The alkenylhalosilanes are water repellents. Rochow (196) prepared alkyl-substituted halosilanes by passing alkyl ether vapors and hydrogen halides over silicon a t 250' to 425' C. Rochow has also patented (196) a process for production of tetramethyl silicate by means of the reaction between gaseous methanol and silica intimately mixed with copper at 150" to 450" C. Pree et al. (188) have patented a process for producing alkylhalosilanes by heating alkyl halides with inorganic compounds containing a t least one hydrogen and one chlorine attached to a silicon atom at a pressure sufficientto liquefy the reactants. Larason (136)has disclosed an improved technique for the preparation of tetraethylsilane using silicon tetrachloride and ethyl magnesium bromide or ethyl magnesium chloride. Yields of 70 to 80% are obtained. Hurd and Yarnall (118) have prepared (pmethoxypheny1)- and (gethoxypheny1)-silicon trichlorides from the Grignard reagent and excess silicon tetrachloride. Meadowcroft and co-workers (161) have patented an interesting process for the continuous production of organosilicon compounds through a Grignard reaction followed by hydrolysis. Bondy and Reiser (17) have prepared organosilicon compounds by treating an alkyl orthosilicate with an organic halide and an alkali metal. A British patent ( 1 ) describes the similar preparation of alkyl-substituted silicon compounds by treating a dialkoxy silicon compound with a dialkyl sulfate and metallic sodium. According to another patent (189) a mixture of silicon tetrachloride and methyl sgicate treated with sodium and isoamyl bromide yield is0 AmSi(OMe)8. When PrLi and EtaSiH in ether are refluxed, a yield of 75% PrSiEt8 may be obtained, according to aBritish patent (88). Larsson and Mjorne (186) have applied the new reaction, RsSiNHR' R'NH2, to EtsSiNHEt to obtain the following triethyl (a1kylamino)silanes: hexyl, heptyl, benzyl, 1-phenylethyl, and 2-phenylisopropyl.
+
METAL ALKYLATION The reaction between ethyl chloride and lead-sodium alloy in the production of tetraethyllead is accelerated by the addition of very small amounts of a nonquinoid ketone according t b a patent by Holbrook (106). It is claimed that a carboxylic acid vster such as (Et0)pCO or CICOsEt and amides such as acetamide .or benzylamide also accelerate the reaction. Plunkett (181) claims that tetraethyllead is catalyzed by small amounts of an acetal containing zero to two chlorine atoms and preferably only
16S7
two atoms. Such compounds as CH2(OMe)2,MeCH(OEt)$,and CICHzCH(0Et)g are specificallyclaimed. The synthesis of ethyldichloroarsine and related compounds by means of the alkylation of arsenic trichloride by tetraethyllead has been described by Kharasch and co-workers (187). Reid and Ubbelohde (186)have investigated the effect of metallic impurities in magnesium on the formation of Grignard compounds. When ethyl iodide reacted with pure magnesium, the products were: 90 to 90.8% ethyl magnesium iodide, 4.4 to 5.9% butane from the Wurtz reaction, and 2.3 to 3% ethane and ethylene formed by disproportionation. The quantity of ethyl iodide consumed in side reactions was not increased by alloying magnesium with aluminum, but some alkyl aluminum compounds were formed. Kabachnik and Shepeleva (1,@3) in an investigation of the course of an organomagnesium synthesis found that MeMgI and PSCls in ether treated with sulfuric acid (10%) gave the dimer, (Me2PS)z. Treatment of this product with nitric acid gave methylphosphinic acid, MenP02H, which upon treatment with thionyl chloride gave dimethylphosphinyl chloride. Rochow (194) has patented a process whereby dimethylgelmanium dichloride is produced from gaseous methyl chloride and germanium associated with a metallic catalyst such as silver or copper. Alkylated boron compounds are prepared from boron halides and alkyl halides in a British patent (80). Trimethylboron was prepared using aluminum or zinc catalyst. The preparation and properties of three complex metal alkyls, LiBMe,, LiAIMe,, and LiaZnMea, are described by Hurd (118). As an example anhydrous aluminum chloride in ether was added to methyl magnesium bromide to form trimethyl aluminum which was added to an ether solution of methyl lithium; the ether was evaporated and the mixture was heated in vacuo at 80' C. to give solid LiAIMe, which is stable only in dry air. Mowery (161)has prepared alkylmercury derivatives of N substituted aromatic sulfonamides by treating mercuric oxide with tetraalkyllead in the presence of an acid whose lead salt is water-soluble, and then treating the mercury compound with the sulfonamide in an aqueous alkaline solution. Haroda (91) describes the making of alkylation compounds with the aid of sodium in liquid ammonia
EQUIPMENT An article by Flowers (69) discusses the safe handling of hydrogen fluoride in a petroleum refinery. Waddill (,973) has patented a method of reducing diffusion of hydrogen fluoride into the pressurizing gas in storage tanks. In this method, a layer of heavy alkylate, boiling between 350" and 500" F. and having s densitj less than that of the hydrogen fluoride, is floated on the surface of the liquid hydrogen fluoride. According to Wachter (Rf), corrosion of iron and steel equipment used in hydrogen fluoride catalytic reactions can be prevented by the use of halides of antimony, arsenic, or bismuth. Fisher et al. (68)have patented an apparatus for alkylation of isoparaffins with olefins in the presence of sulfuric acid, in which a high internal ratio of isoparaffins to olefins is maintained regardless of the external ratio. Another alkylation apparatuq is described by Kanhofer (186)comprising a mixing and centrifuging zone, the liquid catalyst being continuously returned for reuse. Weinrich and co-workers (879) have devised an alkyl&tion process whereby the kinetic energy derived from pumping the hydrocarbon reactants is used for the mixing. This is accomplished by introducing the reactants through a jet orifice set at an acute angle and projecting slightly through the wall of a round-bottomed reaction vessel. A catalyst settling zone over the reaction zone permits removal of spent catalyst and addition of fresh catalyst. Jones (188) emulsified isoparaffins and olefins with sulfuric acid by subjecting them to a 2000- to 5000pound shearing pressure by use of a homogenizer valve in their process for alkylating isoparaffinswith olefins.
I N D U S T R I A L A N D E N G I N E E R I N G CHEMISTRY
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ACKNOWLEDGMENT It is a real pleasure t o acknowledge the valuable help in searching, checking, and abstracting the literature contributed by John I
