Production of Benzyl C J
LABORATOKY AND -Anticipated large scale yroductioii of benq I chloride. coupled with the shortage of toluene for this purpose, led to an investigation of the chloromethylation of benzene an a possible source of henzyl chloride. Laboratory and pilot plant studies show the effects of hydrogen chloride addition at atmospheric pressure arid 50-100 mm. mcrciiry aboTe atmospheric pressure, temperature, speed of agitation, speed of hydrogen chloride addition and total amount
31. H. ChNNOh-, F. L. CAKNAI-fAN, 1). S. CKYDER,
obe 44.3 kp.-cal. per mole. The valuc FfJ calculated riot:s not include other thermal efferts--for examp!cl, the effect of hydrogen chloride on the heat, of solution of z i n c rhloride anti the formation of by-produck Considering all t h w complications which cannot br properly accounted for in t,he calculaI ions, it is believcvl thw t Iht, heat of reaction is ahout 40 kg.-cal. pcsr molts. Several experiments werv made in i i calorimeter, 2nd the red t s indicate that, the calculated value is nearly corrwt :ind suficiwrt,ly Ftccurate for prcwnt ~?urpor;ee: Heat Liberated, Kg.-Cal./AIi+ .Found Calcd. ~
Yield oi Benzj-l Chluricjc, 100 (theoretical) 71 62
zinc chloride appears t o a c t merely as a dehydrating agent, it is' believed that the latter agent is a specific catalyst. Some support for this theory is found in the fact that the substitution of thionyl chloride for zinc chloride fails to produce even a t,race of benzyl chloride. In practice, the zinc chloride-catalyzed reaction b e t w'(,'11 henzene and formaldehyde in the presence of gaseous hydrogel1 chloride is found to be quite exothermic. An estimate of this heat. of reaction can be obtained from a calculation of the heats of formation of the products and reactants and from the less reli:ible, available data on the heats of hydration of zinc chloride and hydrogen chloride. The following heats of formation rvere calculated from the heats of combustion :IS given in the Interna,tionel Critical Tables (C), with the excrptior~of the heat of combustion of benzene which is the value reported by Huffmari ( 3 ) ; the heats 1 Present Charleston, 2 Present 3 Present N. Y.
0;
37
Laboratory
..
96
23 12
44.3 28 25 1 .i
S t.udies
In the laborat,ory the ~tiloromethylationiof h e n z w e \vas s u h ject,ed to a number of reaction variables. The work was divided into t w o parts: (1) experiments conducted with hydrogen chloride a t atmospheric pressure and (2) experiments in R closed system :it, prcssures slightly i n excess of atmospheric.
xmioSPHEKIC IWE ss UHE E X Y E R ~ I ~s- T ,Imixture wnsisting of 1molt: of paritf'ormaldphydt:, 0.99 iiiole zinc chloride, and an excess of benzene was placed in a otielitcxr, three-neck, round-bottom flask, equipped with an efficient 8-inch-blade mercury-seal stirrer of about 600 r.p.m., a thrrniometer, ri reflux condenser, and hydrogen chloride inlet :uid ex$ tnbcs. The hydrogen chloride flow train consisted of maiiostatic controls and a U-shaped flowmeter capable of supplying the system n-ith a constant flow of gaseous hydrogen chloride a t any ired rate. It was found necessary t o place the inlet tube as r the bottom of the renction flask as possible, so that ahsorplit
address, Carhide and Carhon Chemicals Corporation, South
W. Va. address, ~ l a l i i n o k r o d tChemic:al F o r k s , S t . Louis, >Io. address, E. I. dii Pont de Nemours & Company, Inc., Buffalo.
478
bv Chloromethvlation of Benzene J
J
PILOT PLANT STUDIES used, replacement of zinc chloride with zinc oxide, iron and copper halides, preheating reactants before addition of hydrogen chloride, paraformaldehyde-benzene ratio, and reaction time. Distillation of benzyl chloride under various conditions has been studied. Results indicate that benzyl chloride can be prepared in yields of 70% or better, and that the zinc chloride catalyst can be regenerated and re-used repeatedly. '
tion of hydrogen chloride i n the catalytic medium was assured. During the addition of hydrogen chloride, the temperature rose t o 50" C. where it was maintained by cooling with an ice water bath. The rate of the temperature rise was found t o be dependent upon the hydrogen chloride flow rate (Table I). About 3040 minutes after the start of the reaction, the mixture required warming with a hot water bath for the remainder of the reaction period. In some experiments where the addition of hydrogen chloride was slow, t h e reaction mixture was heated t o 50" C. and stirred before the gas was added. I n atmospheric pressure experiments a n excess of hydrogen chloride larger than t h a t required in the closed vessel reaction (described later) was needed. X o attempt was made in this phase of the work t o recover or measure the amount of hydrogen chloride escaping from the reaction vessel. Any deviations from these generalized procedures, qs well as t h e hydrogen chloride flow rates used, are given in the last column of Table 11. The average reaction time amounted to approximately one hour. All products were thoroughly washed successively with two 200-ml. portions of water, two 200-ml. portions of 5% aqueous sodium bicarbonate solution, and finally again with 200 ml. of water. The combined aqueous washings were extracted once with 50 ml. of benzene, and the benzene layer was added t o the organic product. The product was dried over approximately 50 grams of calcium chloride, filtered, and fractionated. All distillations were carried out a t reduced pressures (150100 mm. mercury for benzene and 30-2 mm. for benzyl chloride) in an efficient fractionating column, approximately 2 feet in length and 0.75 inch in diameter, packed with '/*-inch lass helices. The holdup in this column was estimated t o be a%out 5% of the total benzyl chloride yield. This correction was not included in the yield figures given in Table 11. Since benzene was used in excess, the unconverted benzene was recoverable upon distillation. Recovery figures amounted t o a n average of about 50% based on the total benzene present. RUNS AT SLIGHTLY ELEVATED PRESSURES
LVith the exception of a few changes, the laboratory procedures for the chloromethylation of benzene in a closed system a t slight1 elevated pressures (about 860 mm. mercury absolute) n-ere t1e same as those described for the atmospheric runs (Table 111). The hydrogen chloride exit tube used in the atmospherir
pressure experiments was replaced by an adjustable mercury n ell, so t h a t internal pressures up t o about 100 mm. mercury above atmospheric could be maintained in the reaction vessel. The stirrer used was capable of about 1600 r.p.m. Since a closed reaction vessel was used the hydrogen chloride flow train was also omitted; instead, hydrogen chloride was passed into the tared reaction flask, and subsequently the amount adsorbed was determined by weight. Previously air had been flushed from the flask with hydrogen chloride. It was also found t o be more convenient and time saving t o replace the 2-foot distillation column by a shorter, less efficient column. The boiling points of benzene and benzyl chloride justify this change without affecting the yield or the purity of the benzyl chloride obtained. All materials used were commercial grade. For best results the benzene should be a t least 95-97y0 pure. Inferior grades were found t o cause emulsification of the reaction product with water. Granular anhydrous zinc chloride was used in all runs except where it is indicated that stick zinc chloride was the material. The higher boiling residues consisted almost entirely of p-xylylene dichloride, ClCH-CeH.,-CH&l (melting a t 9999.5" C.) REACTION VARIABLES
Comparison of Tables I1 and I11 shows that the chloromethylation of benzene proceeds along identical paths in both processes. The effects of reaction variables, such as rate of stirring, catalyst composition, reaction time and temperature, method of hydrogen chloride addition, and molar ratio of benzene to formaldehyde, as well as the yields and quality of the product obtained, are identical within the limits of experimental errors. Although the method of adding a given quantity of hydrogen chloride has similar effects in both.proceddres, the two vary in the total amount of hydrogen chloride required t o produce similar yields. Thus, a t atmospheric pressure a n excess of 3 t o 4 moles of hydrogen chloride minimum per mole of paraformaldehyde is required for high yields; as shown by run 38, Table 11, only 1.1 moles are actually absorbed by the reaction medium. In this respect the closed-vessel procedure is superior since the reaction medium is supplied with hydrogen chloride a t 50-100 mm. mercury pressure as required by the reaction mixture. This amounts t o about 1.2-1.7 moles of hydrogen chloride per mole paraformaldehyde. As previously shown by Lock (6),the chloroTEMPERATURE. methylation of benzene proceeds sluggishly and i n low yields a t temperatures below 50' C. Contrary t o the results of Lock, the reaction proceeds well a t temperatures greater than 50" C., up to about the boiling point of benzene. It is concluded .that a minimum temperature of 50" C. is preferred. Results of several experiments showing .the effect of reaction temperature follow: Expt. No
37 3, 4
6 49, 48, 50
43,45,46 8
TABLE I. TIME-TEMPERATURE DATA
9
Temp. at HCl Flow Rate of: 4 moles/hr. 6 moles/hr.
Time, hlin.
51 59
25' C. 0 250 c. 31 5 36 10 38 50" 50a 50 15 50 50b 30 47b 35 50 50 60 50 'a Cooling applied with ice water bath. b Drop in reaction temperature, heat applied for remainder of reaction period.
*
Temp.,
71 60 50
60 50 60
40 50 30
' C.
Benzyl Chloride Yield, %
68,70 42,44 43 51, 58, 57 54,59, 56,61 57 47 66 41
The runs in this table are comparable as sets, as shown. Each set was conducted under closely identical conditions. HYDROGEN CHLORIDE-PARAFORMALDEHYDE RATIO. Chloromethylation of benzene a t atmospheric pressure requires a larger excess of hydrogen chloride than does the closed vessel procedure. This is probably due t o the limited solubility of hydrogen chloride in the reaction mixture. A large excess might, therefore, con479
INDUSTRIAL AND ENGINEERING CHEMISTRY
480
Vol. 38, No. 5
. DATAON CHLOROMETHYLATIOX TABLE11. REACTIOX EXPERIMENTS AT ATMOSPHERICPRESSURE
Reactants, 1Ioles C8Ha (CH20)z ZnClz 1 0 0 22 384
Expt. No. 1
(Stirring rate, 600 r.u,m. unless indicated otherwise) Yield Benzyl Reaction Condit9io Chloride Based on sti11 Temp., Time, (CHz0)z Residue, lfoles Grams '7, Grams C. llin. 1 60 20 10 2 8 18 4
~~~~l HCI,
2 3
3 84 3.84 3.84
1.0 1.0 1.0
0.22 0.22 0.22
2 2
GO 60
60 60 60
36.0 53.7 55.6
28 42 44
37.3 28.8 34.2
5
3.84 3.84 3.84 3.84 3.84 3.84
1.0 1.0 1.0 1.0 1.0 1.0
0.22 0.22 0.22 0.22 0 22 0.22
1
7 8 9 10
2 1 3 3 4
50 50 50 50 40 50
30 60 60 60 60 60
20.0 53.9 31.8 72.2 59.8 79.7
16 43 25 87 47 63
22.6 42.9 18.1 21.7 20.2 20.6
11
3.84
1.0
0.22
6
50
GO
78 3
62
20.8
12
3.84
1.0
0.22
4
50
GO
82.8
65
21.4
13
5.13
1.33
0.33
6
60
75
111.9
66
30.4
14
5.13
1.33
0.33
4
30.50
75
109.1
65
23.1
15
3.84
1 0
0.22
4
50
GO
87.3
69
10.4
16
3.84
1.0
0.22
5
50
60
86.1
68
16.6
16.3
4
6
1
60
17
3 84
1.0
0 22
7
50
60
84.1
66
18
3.84
1.0
0.22
9
60
60
83.1
66
..
4
50
60
88.7
70
11.4
4
50
60
84.7
67
1F.8
19 20
Same as 18, b u t 1 mole trioxymethylene used in place of (CHz0)x Same as 19
21
6.13
1.33
0.33
4.8
50
75
112.1
66
24.0
22
3.41
1.33
0.33
4.8
50
75
103.2
61
34.3
23
2.56
1.33
0.33
4.8
50
75
107.7
61
28.5
ceivably furnish the reaction mixture with an amount of dissolved hydrogen chloride a t any given time in sufficient concentration to bring about the reaction a t a fast rate. Even though the process theoretically requires only one mole of hydrogen chloride per mole of paraformaldehyde, the data show that a t atmospheric pressure a t least 4 moles of hydrogen chloride must be passed throuph the reaction mixture to obtain satisfactory yields. I n run 38, Table 11, only 1.1 moles of hydrogen chloride are absorbed by the reaction mixture during the course of the reaction. This figure is in reasonably good agreement with the amount of absorbed hydrogen chloride encountered in the closedvessel procedure. The following data show the effect of variable amounts of hydrogen chloride per mole of paraformaldehyde on the yield of benzyl chloride obtained a t atmospheric pressure: Expt. No. 6.7 6 8 10,12 11
17
18
Moles HCI/ Mole (CHnO). 1 2
Benzyl Chloride, % 16,25
4 6 7
63,65 62.70 66 66
Z
9
45 51
METHODOF ADDINGHYDROGEN CHLORIDE.In the atmospheric pressure procedure a minimum of 4 moles of hydrogen
Remarks HCI introduced a t flow rate of 1.14 l./min. for 20 min. HC1 introduced a t 0.37 l./min. for GO min. HCl introduced a t 0.75 l,/iiiin, for 60 nlin. 1 mole HCI introduced iri first 30 min. a t 0.75 l./min. allowing normal rise in tenll,.: 1 mole HC1 iiitroduced in secoiid 30 rnin. a t 60' C. HCl iiitroduced a t 0.78 l./min. for 30 min. HC1 introduced a t 0.75 i./min. for 80 inin. HCI introduced a t 0.37 I./inin. for BO niin. HCi introduced a t 1.12 I./rnin. for GO min. Same as 8 HCI introduced a t 1.49 l./min. for 60 niiii.; check run produced 81.6 g. benzyl chloride B: 27.5 g . still residue HCI introduced a t 2.24 l./min. for 60 inin.; check run produced 88.1 6.beiiayl chloride 8: 23.6 g . still residue 3 moles HCl introduced in first 20 min. a t 3.30: !./ymln.: 1 niole LICl iiitroduoed in renianiing 40 min. a t 0.56 l,/iiiiti. HCl iiitroduced a t 2.24 l.,'niin, uuriiig fiwt G O r r h . ; reaction tcnip. hi,Id a t 30' C. for first 15 inin,, then a t 50" for remaining reaction ~ e r i o d 2 moles HCI introduced a t 30' C. in first 20 niin. a t 2.24 l./rnin.: 2 riioles IICI introduced a t 50" iii reriiainilix 5 3 niiii. a t 0.80 I./min. Reaction mixt. heated to 7G0 C. for 15 min. prior to llC1 addition: 3 ~ n o l e sh C i iiitruduced a t 50' C . in f i r s t 30 niiii. a t 2 . 2 4 l./min.; 1 mole tic1 iiitroduceii a t 50' C. for remaining 30 iriin. a t 0.76 i./iiiin.: check run produced 83.5 g . heiizyl chloride B: 31.7 g. still residue Reaction rnixt. preheated t o 70' C . for 16 min. prior to llC1 addition: 4 molcs lICl introduced a t 3.99 l./min. for first 30 niin.; 1 mole HCI introduccd in reinaininp 30 min. a t 0.75 I./niiri. Same as 18 except 6 moles EC1 introduced iii first 30 inin. a t 4.48 !./min. Sanie as 1 G except, 8 inoles IlCl introduced in first 30 iiiiii. a t 5.97 l./nnn, Same as 16 except 3 irioles IICl iritroduccd in first 30 min. a t 2.94 I./min. Same as 10 but no preheating of reaction mixt.; check run, using Mercli'a U . S 1'. ZiiCli sticks in place of gmiiular ZirCls, produced 85.0 g . benzyl chloride Bi 23.5 g. still residue HCI introduced in first 15 min. a t 7.1 l./min,: check run produced 110.8 6. beiidyl chloride & 29.3 g. still residue Same as 21 but less benzrne used: check run produced 105.8 g. benzyl chioride B: 30.9 g. still residue Same as 22 but less benzene used: much eniulsification on water washing of product: addition of more bpiizeiie ur N d 1 necessary to break emul-iiuu: check run produced 96.7 g. benzyl chloride B: 32.3 g. still residue
chloride per mole of paraformaldehyde is required, thcroforc, it was of int,erest to determine whether this amount should be introduced into the reaction mixture a t any part'icular rate or . whether it should be introduced rapidly in the initial phases of the reaction, as is general practice in closed vcsscl proccdure. The following results show that the yields of benzyl chloride are independent of the rate of hydrogen chloride passage. Since the rate of heat liberation in the reaction is directly proportional to the rate of hydrogen chloride passage, controlling the reaction by means of hydrogen chloride rate finds immediate application in larger scale operations. Benzyl Chloride, Expt. No. 10 12 15,19 21 16 18 17
Moles of HC1 Added, in 4 in 60 3 in first 20, 1 in next 3 in first 30, 1 in next 4 . 8 in first 15 4 in first 30, 1 in next 6 in 60 6 in first 30, 1 in next
hlin. 40 30 30 30
%
63,65 65 69,70 66 68 70 66
I n the closed-vessel procedure, experiments 43, 45, 46 (Table
111) a t 50' C. show no effect of opening the reaction vessel to the atmosphere after the rapid absorption of hydrogen chloride has ceased. A longer stirring period (experiment 46) has no effect in
I N D U S T R I A L A N D E N G*INE E R I N G C H E M I S T R Y
May, 1946
481
TABLE 11. (Continued)
Reactants, Moles (CHz0)z ZnCh 0.22 1.01
(Stirring rate, 600 r.p.m. unless indicated otherwise) Yield Benny1 Reaotion Conditions Chloride Based on Still Total Temp., Time, (CHzO)z Residue, HCl, Grams * C. Min. Moles 45 61.5 49 20.0 4.8 50 ~
Expt. NO. 24
CeHe 3.84
25
3.84
1.01
0.22
4.8
50
60
77.3
61
16.9
3.84 5.13
1.01 1.33
0.22 0.33
4.8 4.8
50 50
75 60
80.3 160.8
63 63
12.8 23.7
28
5.13
1 33
0.33
4.8
50
75
...
71
22.9
29
5.13
1.33
0.33
4.8
50
75
...
70
33.2
30
5.13
1.33
0.33
4.8
50
75
...
74
17.5
31
5.13
1.33
0.66
4.8
50
75
...
76
21 .o
32
5.13
1.33
0.66
4.8
50
75
...
78
13.5
33
5.13
1.33
0.66
4.8
50
75
...
70
32.8
34
5.13
1.33.
0.33
4.8
50
75
...
70
22.3
35
5.13
1.33 0.33 ($0.1 g. FeCla)
4.8
50
75
...
68
32.2
36
5.13
1.33 0.33 (+0.1 g. CUC12)
4.8
50
75
...
71
33.4
37
5.13
1.33
0.33
4.8
71,50
75
...
68
38.1
38
5.13
1.33
0.33
4.8
60
15
55.3
33
28.1
3.84
1.0
0.22
4.8
50
60
86.4
68
17.1
3.84 3.84 3.84
1.0 1.0 1.0
0.22 0.22 0.22
4.8 4.8 4.8
50 50 -50
60 60 60
70.8 55.0 17.3
56 43 14
12.7 7.2 8.3
26 27
40 41 42
.
(fQ.1g. iron) .
conjunction with a short hydrogen chloride passage. Experiments 48, 49, and 50 illustrate this same point a t 60" C. This behavior is readily explained by the fact that the mixture absorbs the maximum of about 1.5 t o 1.7 moles hydrogen chloride in about 15 minutes at a fast flow rate. PREHEATING OF REACTIONMIXTURE. Heating of the reaction mixture, consisting of benzene, paraformaldehyde, and anhydrous zinc chloride, a t approximately 70" C. for 15 minutes prior to the addition of hydrogen chloride a t 50" C., results in the lowering of residue weight. This effect is believed to be due to the formation of a n activated complex between formaldehyde and zinc chloride. The following data illustrate the point in question for experiments in which chloride yields are comparable: Preheated Expt.
NonBenzyl Still Residue, reheated Chloride, G./Mole of xpt. NO. % ' (CHz0)z 15 69 14 65 17.4 16 68 20 67 23.5 21 66 18.0 17 66 66 22.1 22 19 70 61 25. aa a Average residue for preheated runs, 13.4 g.; average for nonpreheated runs, 21.4 g.; average decrease, 37.4%. NO.
Benzyl Chloride,
%
Still Residue, G./MOle of (CHz0)o 10.4 15.6 16.3 11.4"
QUALITYOF BENZYLCHLORIDE. The nature of the chloromethylation reaction assures that, with proper fractionation of
Remarks HC1 introduced a t 2.36 l./min. for 4.5 min.: check run produced 68.4 g. bennylchloride & 12.3 g. still residue HC1 introduced a t 1.78 I./min. for 60 min check run produced 74.7 g. benzyl ohlorid; & 16.1 g. still residue HC1 introduced a t 1.42 l./min. for 75 min. Preheated t o 70' C. for 15 min.: HC1 introduced a t 7.1 l./min. in 15 min. HC1 introduced a t 7.1 l./min. in 15 b i n . ; stirring rate, about 1200 r.p.m.; check runs with slightly faster stirring produced 73,.76, 70, & 73% benzyl chloride HC1 introduced as in 2$; ZnClz used over dried ZnCln layer from run 28 employed as make-up for re-use studies, check run produced 76% benzyl ohldride; check expt. in which product was distd. without washing produced 377* benzyl chloride & 66 g. still residue HCl introduced as in 28; second re-use of dried catalyst from 2 preceding runs HC1 introduced as in 28; spent ZnClz layer from previous run concd. t o 75% soln. by wt. HC1 introduced as in 28; second re-use of 75% ZnClz sirup HC1 introduced, as in 28: third re-use of 75% ZnClz sirup; check runs in which undried washed product was distd. yielded '747 benzyl chloride Same as previous runs except fresh catalyst used; effect of metallic iron studied
-
benzyl chloride & 44 g. still residue HC1 introduced as in 34; allowed t o rise t o max. of 71' C. spontaneously & t o cool t o 50' C.. 8: held there: check run on uii-
& absorbed 1.1 mole HCI 56.7 g. of spent ZnClz hydrate (containing 25.36% Zn) mixed with 300 ml. benzene & heated t o 50' C.: 1.0 mole SOCh added dropwise over 30 min. and stirred additional 10 min. after SOClz addition was complete; paraformaldehyde added aa before. 4.8 moles HC1 introduced a t 7.1 l./rnin: for 15 min. Same a8 38 b u t 0.79 mole SOClz used Same as 38 but 0.5 mole SOClz used Same as 38 b u t spent ZnClz hydrate used without SOClz
the reaction product, a very pure grade of benzyl chloride results. I n particular, this procedure offers a means of obtaining readily a grade of benzyl chloride which is free of nuclear substituted chlorine. After one distillation, several of the products obtained were analyzed for chlorine by the Parr bomb method. These results follow, together with the refractive indices found: E m t . No. 16 17 18 19 ..
39 Average Calculated
% .- C1 Found
28.16 27.94 27.91 28.04 28.05 28.02 28.01
nI,O 1.5385 1.5389 1.6387 1.5391 1.5392 1.5389
....
BENZENE-PARAFORMALDEHYDE RATIO. Data from experiments in which the only variable in any one set was the ratio of benzene t o paraformaldehyde show that the yields of benzyl chloride are not dependent on a high benzene-paraformaldehyde ratio so long as the agitator speed is 600 r.p.m. or above. At a low agitator speed, 450 r.p.m., i t is advantageous t o have a high benzene-paraformaldehyde ratio. I n addition, troublesome emulsions result when the product containing the smaller quantity of benzene is washed with water. This could be corrected by adding more benzene to the product or by adding sodium chloride to the wash water.
Val.* 38, No. 5
INDUSTRIAL AND ENGINEERING CHEMISTRY
482
-4T 50-100 TABLE 111. RE ~ C T I O S DATI O S CIILORO\IETHYLATION EXPERIMEKTS
3111. 3fERCURY ABOT'E A4T&10SPHERICPRES>I-lLI
Reaction Conditions
Yield Benzyl H C 1Chloride Based on Temp., Time, flow, (CHz0) z C. min. min. Grams 9; 75 93.0 56 50 75
Expt. NO.
CsHs
43
2.05
1.33
0 33
Total HCI. Moles 1 G
44 45
2.05 2.05
1.33 1.33
0.33 0.33
1.7 1.2
50 50
60 75
60 15
99.7 91.4
59 54
35.4 32.4
46 47 48 49 50 51 52 53 54 55
2.05 2.05 2.05 2.05 2.05 2.05 2.05 2.05 2.05 2 05
1.33 1.33 1.33 1.33 1.33 1.33 1.33 1.33 1.33 1.33
0.33 0.33 0.33 0.33 0.33 0.33 0.33 0.33 0.33 0.33
1.5 1.5 1.4 1.4 1.4 1.5
50 50 60 60 60 50
105 105 75 75 105 75
15 105 75 15 15
103.0 101.5 86.2 98.1 96.4 111.5 104.8 118.5 43.9 109.9
61 60 51 58 57 66 68 70 26 65
37.2 37.3 55.0 43.0 43.6 30.4 32.4 28.8 44.4 32.7
67 69 67 41 34
33.1 31.4 33.4 8.0 23.1
a
Reactants, Moles(CH20)z ZnCh
.
x;
1.5
...
1.5 I .7
75
zs
15 15 75
I J
50 50
75 75
75
--I
56 57 58 59 60
5.13 5.13 5,13 5.13 3.85
1.33 1.33 1.33 1.33 0.75
0.33 0.33 0.33 0.33 0.22
1.6 1.5 1.5 1.4 1.5
50 50 30 30
75 75 75 120 60
120 60
113.2 116.5 113.2 69 4 43 0
60
3
15 15
Still Residue, Grams
61
3.85
0.75
0.22
2 0
50
60
60
50.4
40
21.4
62
3.85
0.75
0.22
4.0
50
60
60
66 5
53
21.6
63
3.85
0.75
0.22
4,O
50
60
60
76.3
60
19.2
64
3.83
0.75
0.22
4.0
50
60
60
72.5
57
13.0
65
3.85
0.75
0.22
2.0
50
_ii)-
30
84.9
67
13.5
66
3.85
0.75
0.22
6.0
50
7.5
60
77.1
61
13 4
67 68 69
3.85 3.85 5.13
0.75 0.75 1.33
0.22 0.22 0.33
4.0 2.0 1.6
50 50 50
2G i .> --,.,
60 30 13
71.0 80.3 113.2
56 63 67
14.2 15.6 33.1
70
5,13
1.33
0.55
1.9
50
--
15
111 . 4
(56
14.3
71 72 73 74 75
5.13 5.13 5.13 5.13 2.05
1.33 1.33 1.33 1.33 1.33
0.50 0.44 0.39 0.33 0.29
1.9 1.8 1.6 1.6 1.4
50 50 50 50 50
75 75
75
15 15 15 15 15
108 1 113.2 91.4 94.7 113.2
64 67 54 56 67
12.1 16.4 15.2 7.5 23.2
76 77 78
2.05
1.33 1.33 1.33
0.29 0.26 0 . 33a
1.4 1.4 2.0
50
-1 -. )
15
2,0Li
IJ
15
101.2 88 0 114 9
GO 52 68
20.4 14.1 10.0
79
5.13
1.33
0.33
1.1
60
15
15
35.3
33
28.1
80
5.13
1.33
0.33
1.1
60
1.i
15
54.2
32
19.5
2.05
I ,I
_I J75
13
Remarki Coiltrol for runs 13-59; check e x y t s . gave 5 5 , 5 5 , B- 61% yields; IlCl passed in as rapidly as absorbed; stirring rate. 450 r.p.m. unless otherwise indicated
39.8
........................
.%fter 15 min. stirred a t a t m . pressure: thus time of HC1 passage was shorter. check run gave 59% benzyl c+loricir. & 37 g. residue Longer stirring Longer stirring
..................... . . . . . . . . . . . . . . . . . . . . . .. . .
Longer stirring Stirring rate, 1230 r.p.m. Stirring rate, 1000 r.p.m. Stirring rate, 1600 r.p.m. Stirring rate, 100 r.p.m. Slower HC1 feed of 4 1,tiniii.: chcck run gave 7'1% benz) 1 chloride & 22.3 e . residue Stirring rate, 1000 r.p.in.
....................
Stirring rate, 1230 r.p.m. Stirring rate, 1500 r.p.m. HC1 introduced a t late of 0.49 l , / i i ~ i i ~ . : stirring rate, 200--800 r.p.m. HCl introduced a t 0.66 1. m i n , : itirrinc rate 200-300 r.p.rn. IiCl introduced a t 1.33 1.; niin,; stirring rate, 200-300 r.p.m. dame a s 62 excent .~Dreheated a t 7 0 O (:. f o r 15 min. a t atrn. pressur(! Reagents preheated to 70' C. for I O min., cooled t o 25' C.; I!CJ a t 1.33 l./min. f o r 60 miii.: stirring rat
