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Vol. 76
From the reaction mixture it was found that the of which involved the action on I of a mixture of volatile amine fraction accounted for 85% or more methanesulfonyl chloride and acetic acid in pyridine of the total nitrogen of the proteins and model a t room temperature. Instead of the methanesulcompounds subiected to hydrogenolysis with copper fonate there was obtained a colorless, sulfur-free chromite a t 230”. The exception was the case of product, identified as 5-acetoxy-3,3‘,4’,7-tetraacetyl zein in which the linkages appear to be partly methoxflavone (11). protected. Less was produced from zein I1 upon Raney nickel hydrogenolysis a t 185”. In every instance of hydrogenolysis the volatile amine fraction gave a negative Nessler test for ammonia; instead the reagent produced a white, chalky precipitate. All of this base in each case was identiOR 0 fied as tri-n-butylamine which was isolated and I,R=H purified as the picrate. All samples melted from 11, R = COCHr 103-105” with no depression when mixed with authentic sample. The nitrogen content by modified The difficulty encountered in attempting to methmicro-Kjeldahl was 12.9%, the calculated value is anesulfonate I is not surprising, since the 5-hy13.5%. However, a value of 12.9% was also ob- droxyl of I is known to be also difficult to methyltained on an authentic sample of tri-n-butylamine ate,2*3 and acetylation has been reported only when picrate. No primary amine nitrogen was found; the vigorous conditions of boiling acetic anhydride such would be expected since the conditions of hy- and anhydrous sodium acetate were used.4 Our drogenolysis favor alkylation, as has been shown acetylation procedure accordingly seems remarkby Adkinsea During hydrogenolysis the amide and able, employing as it does very mild conditions. peptide linkages of the compounds appear to be Experimental attacked to the same extent with conversion of Quercetin 3,3’,4‘,7-Tetramethyl Ether (I) .-Quercetin their nitrogen to the fully alkylated base. was methylated by the method of Waliaschko,6 with retenDuring butanolysis, primary amino nitrogen tion of the product, m.p. 155-157’, considered by Waliwas liberated and ammonia appeared in all products aschko t o be a trimethyl ether, but subsequently showna t o thus confirming Herzig’s contention.* except from nylon and butyl hippurate. No alkyl- be I,S-Acetoxy-3,3 ‘,4’,7-tetramethoxyflavone.-To 0.1 g . of ated nitrogen product was detected. Peptide ni- quercetin 3,3’,4’,7-tetramethyl ether, dissolved in 11 ml. trogen is markedly more resistant to butanolysis of reagent pyridine, was added first 0.7 ml. of glacial acetic than hydrogenolysis ; this is particularly evident acid, then 0.6 g. of methanesulfonyl chloride. Heat was and crystalline material (water-soluble) separated with butyl hippurate and nylon. Furthermore, the evolved, in approx. 30 seconds. The pyridine solution was decanted peptide linkages are more resistant to hydrogenoly- from solid material after 40 minutes, and the pyridine decansis than the primary amide bonds of acetamide and tate permitted to stand a t room temperature an additional 42 hours. The crude acetate was isolated by pouring the polyacrylamide. reaction mixture into 90 ml. of water, and permitting the Hydrogenolysis produced marked changes in the aqueous suspension t o stand for three hours. The crude, forms of nitrogen as revealed by the Van Slyke ni- crystalline solid deposited was collected by filtration, trogen analyses summarized in Table 11. Most washed with water and air-dried for several days; m.p. 165striking is the enormous increase in the “ammonia” 170”. After sodium fusion, the crude product gave negatests for sulfur both with lead acetate and sodium nitrofraction which was all identified as tri-n-butylamine. tive prusside. The crude acetate was recrystallized twice from After butanolysis the “phosphotungstic acid bases” absolute ethanol to give colorless, silken needles, m.p. 169and the “non-amino” nitrogen in the filtrate are in- 171’ (lit. m.p. 167-169’,* 171-17206), no depression upon creased a t the expense of the “soluble amino” ni- admixture with authentic 5-acetoxy-3,3’,4’,7-tetramethoxyflavone (m.p. 169-170.5’), prepared by the method of trogen. Similar but less drastic changes are pro- Herzig.‘ duced upon zein I1 by hydrogenolysis with Raney (2) J. Herzig, Sifrunfsber., 121, 333 (1912). nickel a t 185”; as may also be seen with acetyl (3) Methylation of the 5-hydroxyl of I has been achieved, however, zein. by employment of dimethyl sulfate and solid potassium hydroxide DEPARTMENT OF AGRICULTURAL BIOCHEMISTRY OF MINNESOTA UNIVERSITY ST. PAUL, MINNESOTA
[A. S. Gomm and M. Nierenstein, THIS JOURNAL, 65, 4408 (1931)). (4) J. Herzig, Monafsh., I, 86 (1884). (5) N. Waliaschko, Bcr., 42, 727 (1909). (6) N. Krassowski, Chcm. Ccnlr., 80, [I] 772 (1909).
DEPARTMENT OF CHEMISTRY
A Novel Acetylation of Quercetin 3,3’,4’,7-Tetramethyl Ether (5-Hydroxy-3,3 ’,4’,7-tetramethoxyflavone) BY J. H. LOOKE.R AND F. c. ERNEST RECEIVED AUGUST3, 1953
In an investigation of the methanesulfonation of quercetin and its derivatives, we have observed that quercetin 3,3’,4’,7-tetramethyI ether (I) cannot be rnethanesulfonated by the action of methanesulfonyl chloride in pyridine. Several modibcations of the usual procedure were then employed, one (1) J. H. Looker and A. L. Krieger, unpublished observations.
THEUNIVERSITYOF NEBRASKA h LINCOLN,
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Chlorotetranitronaphthalenes BY WALTERE. MATHEWSON RECEIVED SEPTEMBER 23, 1953
Although two isomeric bromotetranitronaphthalenes were described seventy years ago, no mention has been found in the literature of chlorotetranitronaphthalenes. The two chlorotetranitronaphthalenes described here were prepared mainly for trial as colorimetric
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Jan. 5, 1954
295
reagents. From their similarity to the bromotet- less than 110 parts of boiling 95% alcohol; in two parts of boiling glacial acetic acid; and in less than 14 parts of glacial ranitronaphthalenes studied by Merz and Weith' acetic acid at 25'. It was very soluble in @-dioxane, disone is tentatively designated as 4-chloro-1,3,6,8- solving in about its own weight of this liquid a t 25'. Melttetranitronaphthalene, the other as 4-chloro-1,3,5,8- ing point of crystallized substance after heating for 30 tetranitronaphthalene; the first corresponding to minutes a t IIO', 176'. Merz and Weith's 4-bromo-1,3,6,8-tetranitronaph- Anal. Calcd. for c1&a(N?p)rC1.CsHs: cat, 18.57. (loss on heating for 30 minutes at IIO'), CaHa, 18.48. thalene of melting point 189', the second to their Found: Calcd. for benzene-free substance, C&(NOJ&l: C1, 10.35. 4-bromo-1,3,5,8-tetranitronaphthaleneof melting Found: C1, 10.41. point 245'. The 4-chloro-1,3,6,8-tetranitronaph- 4-Chl0r0-l,3,5,8-tetranitronaphthalene.-This compound thalene in benzene suspension with ammonia gave was nearly insoluble in benzene and in alcohol. It dissolved Merz and Weith's l-amino-2,4,5,7-tetranitronaph-in about 40 parts of boiling glacial acetic acid, approxione-half separating in small yellowish white needles thalene (4-amino-1,3,6,8-tetranitronaphthalene) mately on cooling. It was soluble in 11 parts of boiling p-dioxane of melting point 194'. from which it crystallized in almost white, very fine needles; Merz and Weith prepared the bromotetranitro- m.p. 259'. naphthalenes by a two-stage nitration involving Anal. Calcd.: (212, 10.35. Found: Clz, 10.20. intermediate precipitation of the partially nitrated The chlorotetranitronaphthalenes when dissolved at room material. They mention but do not describe in de- temperature in very dilute alcoholic potassium hydroxide gave intensely red solutions that if tested immediately with tail, a one-stage method which apparently, gave silver salts showed only traces of chlorides. After warming very low yields. The following process is much or standing, the solutions gave heavy precipitates of silver shorter than the two-stage method and gave yields chloride. Both isomers react with simple primary amines, fully equal to those obtained with it. However, the even a t high dilutions, to give deeply colored brown or secondary amines. recovery of purified product was still low, amount- yellow I t is apparent that the chlorotetranitronaphthalenes are ing to some 25-27 parts of crystalline benzene-sol- acids, though not proton donors. However, because of the uble chlorotetranitro compound, and 8-12 parts high lability given to the halogen by the ortho and para crude benzene-insoluble isomer, per 100 parts nitro groups the compounds behave as acid chlorides in chloronaphthalene. For the acid nitration mixture, most of their common reactions. Grateful acknowledgment is made to Dr. J. 0. a smaller amount of oleum of higher sulfur trioxide Maloney for use of the facilities of the Kansas content probably would be better than the 20% fuming sulfuric acid specified; however, it was not University Research Foundation in connection with this work. available for trial a t the time the work was done. Procedure.-One hundred grams (84 ml.) of I-chloro- TOPEKA,KANSAS naphthalene was dropped very slowly into 400 g. (270 ml.) of fuming nitric acid of specific gravity 1.50, the latter being Stability of Chromium Oxides swirled and kept cold in a bath of ice and water. The liquid was then added slowly t o a cooled mixture of 400 g. BY M. A. MOSESMAN (270 ml.) of the fuming nitric acid with 800 g. (435 ml.) oleum or fuming sulfuric acid of 20% sulfur trioxide content RECEIVED AUGUST17, 1953 contained in a two-liter erlenmeyer flask, and kept a t a temperature below 45'. The h s k finally was heated in a boilThe recently described work of Schwartz, Fanking water-bath for one hour after the temperature of the uchen and Ward' on the thermal decomposition of mixture had reached 92'. After cooling, the nitration mixture was poured on crushed ice, the diluted acid syphaned chromium trioxide suggests that the results of some off and the solid washed first by decantation, then in a experiments we conducted along similar lines during buchner funnel (without pressing) until the acidity of the the first half of 1951 might prove of interest. The wash water was below N/100; the drained solid was then objective of these experiments was to establish dried on filter paper supported on a pad of news-print. The granulated material held water very tenaciously, and the stability of a promoted, alumina-supported although all surface moisture soon passed off, it was neces- chromic oxide catalyst under the reducing and oxisary to a i r d r y for several weeks. dizing conditions to which the catalyst is subjected The dry product was extracted with benzene in a large during the process of paraffin aromatization. In soxhlet tube, the soluble fraction crystallizing from the extract, and being further purified by recrystallization from view of the desirkbility of studying such a reaction benzene. Several methods were tried for the purification system in situ by X-ray diffraction, the previously of the benzene-insoluble isomer, crystallization from glacial described apparatus2 utilizing a beryllium microreacetic acid probably giving the best results though the com- actor was employed. pound is not very soluble in this solvent, even a t the boiling The first phase of this work was devoted to a temperature. The crude 4-chloro-1,3,5,8-tetranitronaphthalene was more soluble in boiling p-dioxane but did not study of the thermal stability of bulk chromium crystallize rapidly from the solution. The impurities in the trioxide in order to provide a reference case for subcrude extracted material increased the solubility of the 4- sequent investigation of the above-mentioned catachloro-l,3,5,&tetranitronaphthalene in dioxane and much lessened the tendency toward crystallization. Hot chloro- lyst. Interest in the thermal characteristics of benzene, and hot 2,2'-dichlorodiethyl ether as solvents gave CrOs was predicated on the fact that the general crystals of lower purity. preparative procedure for such catalysts involves the 4-Chloro-l,3,6 ,&tetranitronaphthalene.-This isomer was use of this water-soluble oxide for impregnating soluble in 4 to 4.5 parts of boiling benzene, approximately four-fifths separating on cooling in pale yellow needles con- the support, followed by drying and calcination taining an equimolecular amount of solvent. The crystal- of the resulting mixture a t temperatures sufficient to convert Cr03 to Crz03. After drying for several lized compound when heated in a capillary tube fused and lost benzene a t about 110'; however, 0.5 g. when exposed weeks a t loo", C.P. CrOs was charged to the microin a n open dish a t summer temperature effloresced rather reactor and the apparatus assembled and evacurapidly, about four-fifths of the benzene passing off in 24 (1) R. S.Schwartz, I. Fankuchen and R. Ward, T H i a JOURNAL, 14, hours. The benzene compound was soluble in somewhat (1)
V. Metz and W.
Weith, Ber., 16, 2708 (1882).
1676 (1952). (2) M. A. Mosesman, ibid.. 73, 5635 (1951).
