[CONTRIBUTION FRO11 KOYES CHEMICAL LABORATORY, USIVERSITY
OF
ILLINOIS]
HYDROLYSIS AND OXIDATION OF MUSTARD GAS An'D RELATED COMPOUNDS IN AQUEOUS SOLUTION1 CHARLES C. PRICE* AND ORVILLE H. BULLITT, J R . ~
Received
August
19,
1946'
In order to evaluate more accurately the problems involved in treatment of water contaminated with mustard gas, (P-chloroethyl sulfide, I), the behavior of I and its principal hydrolysis products, thiodiglycol (X) and the sulfonium salt XIV, toward such reagents as hypochlorite, chloramine-?', Halazone (XVII), ozone, and hydrogen peroxide was investigated, especially in dilute bicarbonatebuffered solution. The various transformations by oxidation, hydrolysis, and dehydrohalogenation outlined in the scheme on page 239 were established. Compounds XV and XVI, the dinitrobenzoates of X and XI, and the diacetate of XI1 have not been previously reported. The sulfone sulfonium salt XVI was obtained only as an intractable oil, difficult to purify and characterize. Potamium mercuric iodide was found to be a sensitive reagent for detecting the three sulfonium salts (XIV, XV, and XVI). Using this test, the extent of formation of XIV from hydrolysis of I under various conditions was estimated. It was found that Levinstein mustard4 was considerably more resistant t o dissolution in water than pure I. An investigation of residues from these experiments revealed that, whereas Levinstein mustard undergoes considerable decomposition on vacuum distillation, water-washed material distilled satisfactorily to yield water-white, stable, nearly odorless material. Exhaustive water-washing, however, left a dark, water-insoluble oily residue containing no B-chloroethyl sulfide and consisting of about 20% of the original Levinstein mustard. This material has been carefully investigated by Fuson and coworkers (1) and shown to consist of p-chloroethyl polysulfides. The reaction of three of these, the di-, tri-, and penta-sulfides, with aqueous chloramine-T a t pH 1 led to quantitative cleavage to 6-chloroethanesulfonic acid (and sulfuric acid). (ClCH2CH2)2&
(0)
2ClCHZCH2SOsH
+
(X
-
2)HzS04
(x = 2, 3, 5) 1 The work reported herein was carried out under a contract, recommended by the National Defense Research Committee, between the Office of Scientific Research and Development and the University of Illinois. 2 Present address: University of Notre Dame, Notre Dame, Indiana. 3 Present address: Experimental Station, E. I. duPont de Nemours and Co., Wilmington, Delaware. 4 Prepared by the reaction of ethylene with sulfur monochloride; supplied by the Chemical Warfare Service. 238
239
REACTIONS O F MUSTARD GAS IN WATER EXPERIMENTAL
Ozonization of 8-chloroethyl sulfide in water. To 400 ml. of water, through which oxygen containing about two per cent ozone was being bubbled, 40 ml. of Cellosolve containing (C1CHsCHz)zS
--.EL
(C1CHzCHz)zSO
oc1-_,
(C1CHzCHz)zSOz
(Od
I1 Ha0
1
I11
I
NaHCO:
C1 CHz CHz
CHz=CH
ClCHzCHz
\ /so
/,
\ so2 /
CH2=CH
IV Hz0
I NaHCos
Hao
V NaHCOa
Hi0
(CHz=CH)zSO
1
NaHCOa
(CH2=CH)zSOz
VI
VI1
(HOCHzCHJzS X
I
I
I
1
CHiCHz
/ 0.
hHpo
\
c1-
\
/
so*
c1-
CHzCHz XI11
xv
x
+
XIV
1
KHgIa
/
/
/KHgIs
1(
oily insol. PPt .
c1-
~
KHgIi
+
3(HOCHzCHz)zSOz [(HOCHzCHz)zSCHzCH2]zS0z 3)XVI
XI1
H O O C ~- S O ~ N C L Halazone, XVII 1.6 ml. of 8-chloroethyl sulfide was added dropwise during one hour. On evaporation of the water solution t o dryness and recrystallization of the residue from ethanol, 1.2 g. (53%) of crystalline 8-chloroethyl sulfoxide melting a t 105-108" was obtained [lit. (2), 109.5°]. The melting point of a mixture with a sample of 8-hydroxyethyl sulfoxide waa below 95".
240
C. C. PRICE Ai'iD
0. H. BULLITT, JR.
Reaction of 8-chloroethyl suljide with dilute aqueous sodium hypochlorite. T o 100 ml. of water containing 2.25 millimoles of sodium hypochlorite, adjusted t o pH 7.5 with dilute hydrochloric acid immediately before use, was added 25 ml. of methanol containing two millimoles of 8-chloroethyl sulfide. The solution became slightly warm. After standing one hour, the solution was extracted three times with 40 ml. of chloroform, the extract was dried over sodium sulfate and the solvent was removed by evaporation. There was thus obtained 0.2 g. (57%) of crystals of 8-chloroethyl sulfoxide melting at 105-108". The melting point of a mixture with a sample of 8-hydroxyethyl sulfoxide was 94-100". Reaction of p-chloroethyl sulfide with dilute aqueous chloramine-T. T o 100 ml. of water containing four millimoles of chloramine-T was added 50 ml. of methanol containing four millimoles of P-chloroethyl sulfide. On concentrating the solution t o a small volume, 0.55 g. (83%) of crystals separated. After two recrystallizations from ethanol, these melted at 138-142" and did not depress the melting point of an authentic sample of p-toluenesulfonamido-8-chloroethyl sulfilimine, m.p. 139-142' [lit. (3), 144'1. Remiion of p-chloroethyl sulfide with dilute aqueous Halazone. A solution of Halazone waa prepared by dissolving the solid reagent i n aqueous alkali. A 100-ml. portion of this solution, containing two millimoles of chlorine, waa adjusted t o pH 7 with dilute hydrochloric acid, and two millimoles of 6-chloroethyl sulfide dissolved i n 25 ml. of methanol was added. Bfter ten minutes the solution was neutralized with excess sodium bicarbonate and then evaporated t o dryness under reduced pressure. The solid residue was extracted with ether. Evaporation of the ether solution gave crystals which were recrystallized from ethanol t o give 0.14 g. (40%) of P-chloroethyl sulfoxide melting at 104-107". The melting point of a mixture with an authentic sample of p-chloroethyl sulfoxide was 105-108". Decomposition of 6-chloroethyl sulfoxide in alkaline solution. A 2% aqueous solution of 8-chloroethyl sulfoxide was prepared in distilled water. To 100 ml. of the filtered solution was added 3 g . of solid sodium bicarbonate, which was dissolved by shaking. Almost immediately, crystals of the sulfoxide began to separate from the solution. It was estimated that about half of the original amount precipitated, but the solid was not removed. Within five minutes a portion of the solution was acidified with dilute nitric acid, and a few drops of silver nitrate solution added. No trace of silver chloride was detected. After two hours, a repetition of the test gave a very faint cloudiness. After twenty-four hours the test was definitely positive with a flocculent precipitate of silver chloride forming.5 After two weeks the original solution in distilled water still gave no test for chloride ion. Reaction o j P-chloroethyl suljoxide with aqueous sodium hypochlorite. I . T o 10 g. (57 m.moles) of 8-chloroethyl sulfoxide in one liter of water containing 5 g. of sodium bicarbonate was added 300 ml. of a solution containing 114 millimoles of sodium hypochlorite adjusted to pH 7 with dilute hydrochloric acid immediately before use. After the solution had been allowed to stand overnight, i t was extracted three times with 250 ml. of ether. The ether extracts were combined, dried over magnesium sulfate, and the ether removed by distillation. The residual oil solidified on standing, after the last traces of ether had been removed in uacuo. Recrystallization from ethanol gave four grams (37%) of p-chloroethyl sulfone melting at 54-56' [lit. (2), 56'1. 11. Two hundred grams (1.4 moles) of P-chloroethyI sulfoxide was dissolved in 7.5 1. of water. Into this solution, 4.5 1. of 0.612 N sodium hypochlorite solution (1.38 moles), t o which 100 g . of sodium bicarbonate had just been added, was poured rapidly with stirring. Another 100 g. of sodium bicarbonate was then added. After the reaction mixture had stood overnight, i t was continuously extracted with chloroform for two days. When the solvent had been removed at water-pump pressure, the residual liquid (205 9.) rapidly precipitated a large mass of crystals. Filtration gave 167 g. of liquid, 37 g. of solid. The melting point of the solid was 103-107O, that of p-chloroethyl sulfoxide. The filtrate was subjected to a rapid vacuum distillation from a Claisen flask, b.p. 5 I n contrast t o the stability reported b y Marshall and Williams (4s) and Peters and Walker (4b).
24 1
RESCTIOKS OF MGSTARD GAS IN WBTER
73-145" (1.0 mm.), leaving a black semi-solid residue of 30 g. from which 9 g. of light tan crystals, melting at 107-108" were obtained by washing with acetone. The distillate was then fractionally redistilled through a 12-inch column packed with Berl saddles. The results, summarized in Table I, indicate the presence of vinyl sulfoxide [b.p. 81" (16 mrn.); n: 1.51001 and sulfone [b.p. 109" (16 mm.); n: 1.47821, and j3-chloroethyl vinyl sulfoxide [b.p. 126" (15 mm.); n: 1.52321 and sulfone [b.p. 143" (16 mm.); n : 1.49521 (5,6). The solubility of j3-chloroethyl sulfone in water. A sample of j3-chloroethyl sulfone was recrystallized repeatedly from ethanol until i t failed t o give a precipitate with alcoholic silver nitrate, m.p. 55.0-55.2'. About t e n grams of this sample was placed i n a glassstoppered bottle containing 700 ml. of distilled water. The bottle was kept in a constant temperature bath at 25" for seven days. At intervals i t was removed and thoroughly shaken. At the end of this time the solution gave no test for chloride ion with silver nitrate, and there was still some undissolved sulfone i n contact with the solution. Samples of t h e solution were then transferred to tared weighing bottles; the bottles were weighed and t h e
TABLE I DISTILLATION OF CHLORINATED ~CELOROETHYL SULFOXIDE WEIGHT
m GUMS
2.05 3.05 3.15 2.00 2.25 2.50 3.45 4.90 5.35 9.25 9.30 6.80 6.25 3.65 5.45
B O I W G POINT,
57-53 53-52 53-57 58-70 70-84 53-86 S2-88 88-s9 91 84
s3 81-82 i9-81 81 89-91
'c.
PXESSUXE IN
0.13
.os .os .12 .22 .26 .33 .33 .30 .25 .18 .16
.11 .17 .26
m.
1 .SO40 1.4984 1.4978 1.5053 1.5152 1.5182 1 .5078 1.5007 1.4992 1 .4972 1,4968 1.4962 1 .4962 1 .4962 1.4977 -c
water was then allowed t o evaporate i n a desiccator over calcium chloride. The bottles were dried t o constant weight and the amount of sulfone in a given amount of water thus determined by difference. The melting point of the sulfone recovered from this experiment was 54-55', with slight softening a t 50". A blank experiment i n which weighed amounts of sulfone were placed in the weighing bottles, water added, the water evaporated as above, and the sulfone reweighed, showed that no sulfone was lost by this method. The solubility of the sulfone as determined in this way was 1.115 g. in 100 g. of water. This is about twice that reported by Helferich and Reid (2). After seventeen days the saturated solution still contained no chloride ion as shown by a silver nitrate test. Decomposition of j3-chloroethyl sulfone in alkaline solution. When a 1% solution of 8chloroethyl sulfone in distilled water was made alkaline t o pH 7.8 by the addition of sodium bicarbonate, the solution gave a precipitate of silver chloride within five minutes, while the original solution, p H 5.5, did not give a similar precipitate after two weeks. T o a solution of 10 g. (0.052 m.) of 6-chloroethyl sulfone i n a liter of water was added 16.8 g. (0.2 m.) of sodium bicarbonate. After standing overnight, the solution gave a positive test for unsaturation with potassium permanganate and with bromine in carbon tetrachloride. The solution was extracted with ether i n a continuous liquid-liquid ex-
242
C. C. PRICE AND 0. H. BULLITT, JR.
tractor for sixteen hours. Evaporation of the ether solution gave two grams of residual oil. Distillation of this material gave 1.6 g. of vinyl sulfone, boiling at 110' (17mm.) ; 71 1.4750 [lit. (6),b.p. 109" (16 mm.); n: 1.47821. The preparation of 8-hydroxyethyl sulfone. Following the procedure of Gilman and Beaber (7),5 g. (0.04mole) of thiodiglycol was dissolved in 10 ml. of glacial acetic acid, and 11.5g. (0.1mole) of 30% hydrogen peroxide was added slowly in the cold with stirring. The resulting mixture was then heated on the steam-bath for two hours, after which the solvent was removed by distillation at reduced pressure. An oil was thus obtained which would not crystallize on cooling, drying over phosphorus pentoxide, or rubbing under various solvents. An attempted distillation of this material gave a n oil boiling a t 130-140" (1 mm.), which solidified on cooling and, after recrystallization from butanol, melted at 129-130". The melting point and analysis indicated this t o be thioxane sulfone [lit. ( 8 ) , m.p. 130"]. Anal. Calc'd for C I H ~ O ~ C, S : 35.30;H, 5.88. Found: C, 35.50;H, 6.36. Crystallization of the undistilled oil could not be induced by seeding with thioxane sulfone. The method of Lewin (5)was then followed to obtain crystalline p-hydroxyethyl sulfone. Perbenzoic acid was prepared as a 0.51 M solution in ether using the procedure i n Organic Syntheses. A mixture of 100 ml. of absolute ethanol, 80 ml. of chloroform and 5 g. (0.04 mole) of thiodiglycol was cooled t o -5" and 200 ml. (0.1mole) of the perbenzoic acid solution was added. After allowing the solution t o stand for twenty hours, the solvents were removed by evaporation a t reduced pressure. The residue was taken up in ether and cooled in a dry ice-acetone bath until crystals were obtained. After three recrystallizations from ether, the melting point xas 54-55". When the oil prepared from the hydrogen peroxide method was rubbed under ether or acetone and seeded with crystals from the perbenzoic acid reaction, crystallization finally occurred. It was found more convenient t o use acetone for recrystallization, since cooling to 0' was then sufficient, but seeding was always found necessary with this solvent. The compound was rather difficult t o purify in any case, and the melting point reported by Lewin [57-58' (5)l was never attained. Ozonization of thiodiglycol in water. Oxygen containing 2.5% ozone was bubbled through 100 ml. of water containing 1.6 g. (0.013mole) of thiodiglycol for ninety minutes at a rate of 200 ml. of oxygen a minute. Thus 0.02 mole of ozone was passed into the solution. On evaporating the water and drying the residue in a desiccator over phosphorus pentoxide, 1.7 g. (95% yield) of slightly oily crystals were obtained. After one recrystallization from n-butanol, the melting point and the melting point of a mixture with an authentic sample of p-hydroxyethyl sulfoxide were both 106-108" [lit. (5),112'1. A solution of 4.7 g. (0.031 mole) of 8-hydroxyethyl sulfoxide i n 200 ml. of water was treated with 0.65% ozone at one liter per minute for three hours, thus applying 1.5moles of ozone per mole of sulfoxide. The solution was then evaporated to dryness leaving a crystalline residue which was extracted with three 10-ml. portions of acetone. There then remained 3.3g. of material, melting point and melting point mixed with an authentic sample of 8-hydroxyethyl sulfoxide, 105-108". The acetone w'as removed by evaporation leaving a n oil which solidified on rubbing under dry ether to give 1.0 g. of crude P-hydroxyethyl sulfone melting at 36-43', a conversion of 20% and a yield of 64% based on unrecovered starting material. After one recrystallization from acetone, the melting point was 50-54'. Reaction of thiodiglycol with dilute aqueous chloramine-T. T o 375 ml. of water containing 3 g. (0.025mole) of thiodiglycol buffered t o p H 6.9 was added 0.025mole of chloramine-T in 100 ml. of water. On partial evaporation of the resulting solution, about one gram of solid separated and was removed by filtration. The melting point was 133-135" (lit. for p-toluenesulfonamide, 137"). The solution was then evaporated t o dryness and the solid residue extracted with hot butanol. On cooling, 1.7g. (50% yield) of crystals of &hydroxyethyl sulfoxide separated from the butanol. The melting point and melting point of a mixture with a n authentic sample were 108". Reaction of thiodiglycol with dilute aqueous Halazone. To 10 ml. of water containing 4.28
REACTIONS O F MUSTARD GAS IN WATER
243
millimoles of thiodiglycol was added 100 ml. of water containing 4.28 millimoles of chlorine as Halazone. The Halazone solution had been made up from solid Halazone and dilute alkali and was acidified with dilute hydrochloric acid to pH 7 immediately before use. The solution was concentrated to a small volume by evaporation a t reduced pressure and acidified. The p-sulfamylbenzoic acid which precipitated was removed by filtration. The solution was then evaporated t o dryness and the solid residue extracted with hot butanol. On cooling the solution, 0.45 g. (76% yield) of crystalline P-hydroxyethyl sulfoxide separated. The melting point and melting point of a mixture with a n authentic sample were 106-108". Reaction of thiodiglycol with dilute aqueous sodium hypochlorite. T o 1.65 g. (14.4 m.moles) of thiodiglycol was added 200 ml. of 0.1444 N sodium hypochlorite solution (14.4 m.moles). The hypochlorite was prepared by passing chlorine into a solution of sodium hydroxide, standardized by titration of the iodine liberated by a n aliquot with standard sodium thiosulfate, and adjusted to pH 7 with dilute hydrochloric acid immediately before use. The resulting solution was neutralized with excess sodium bicarbonate and then evaporated t o dryness a t reduced pressure. The residue was extracted with hot butanol. On cooling the butanol solution, 1.2 g. (60% yield) of crystals were obtained. The melting point and melting point of a mixture with 8-hydroxyethyl sulfoxide were 106-108'. Solutions of thiodiglycol containing from one t o ten grams of glycol per 100 ml. of solution were treated with chlorine both by bubbling in an excess of chlorine and by adding a n excess of neutral sodium hypochlorite solution as prepared above. In every case the reaction proceeded vigorously with the evolution of appreciable heat in the more concentrated solutions. Neutralization of the solutions with sodium bicarbonate , followed by evaporation at reduced pressure, extraction of the residue with dioxane, and evaporation of the dioxane gave oils from which thioxane sulfone was obtained in good yields by distillation, as described in the preparation of 8-hydroxyethyl sulfone. A test for the sulfonium salt ( X W ) in water. Stock solutions of chloroplatinic acid, chlorauric acid, mercuric chloride, mercuric iodide, and picric acid in water were used. A few drops of each reagent were added to aliquots of successive dilutions of the sulfonium salt (9) in mater. By observing the dilution at which the insoluble solid or oil, formed by the addition of the reagent, was just barely detectable, i t was found that the complex formed with mercuric iodide was the least soluble and therefore most suited for development as an identifying test. A solution prepared from 26 g. of potassium iodide, 45 g. of mercuric iodide, and 20 ml. of water was used in subsequent tests. The addition of 0.02 ml. of this solution to 2 ml. of the solution being tested gives a noticeable white cloudiness in the presence of 10 mg./liter of the sulfonium salt in water. A solution containing 5 mg./liter did not give a positive test under these conditions. It is important that the results of the test be observed within five or ten seconds after addition of the reagent and that the cloudiness be creamy white, since addition of the reagent to distilled water produces a reddish-gold crystalline precipitate after about thirty seconds. Formation of sulfonium salts during the hydrolysis of 8-chloroethyl suljide. One hundred milliliters of distilled water and 0.64 g. of P-chloroethyl sulfide were shaken together in a glass-stoppered flask until complete solution had occurred. A sample of the resulting solution was diluted until it just gave a positive test for the sulfonium salt with the potassium mercuric iodide reagent. The dilution factor of the most dilute solution to give a test was 100. The original solution therefore contained about 1000 mg. of the sulfonium salt per liter. Thus about 16% of the P-chloroethyl sulfide was converted to sulfonium salts. The experiment was repeated using a phosphate buffered solution, the pH of which fell from 7.3 to:6.4 during the experiment, and also using a bicarbonate-buffered solution in which the pH fell from 7.9 to 7.4. I n the first case, the original solution gave no test for the sulfonium salt while in the latter the dilution factor was 30. Thus there was less than 0.1% sulfonium salt formation in the first case and about 5% in the second. Preparation of the sulfonium salt sulfoxide ( X V ) . To 20 g. (0.05 mole) of the sulfonium salt (9) as added 5.7 g . (0.05 mole) of 30'% hydrogen peroxide. The mixture was stirred
244
C. C. PRICE .4SD 0. H. BULLITT, JR.
until complete solution occurred and then poured into an evaporating dish. Water mas first evaporated in a stream of dry air, then over calcium chloride, and the last traces of moisture removed in a vacuum desiccator over phosphorus pentoxide. After standing several weeks in the desiccator, the compound finally solidified t o a yellowish mass of crystals. The material was so strongly deliquescent that i t could not be dried by means of calcium chloride. Purification had t o be carried out in an atmosphere dried over phosphorus pentoxide. The salt was insoluble in all ordinary solvents except water and methanol. I t was recrystallized by dissolving in a small amount of methanol, adding absolute ethanol t o incipient cloudiness, and then chilling the solution in a n icebox for several days. Rosettes of needle-like crystals first formed on the sides of the flask and then spread throughout the solution. After two recrystallizations, the melting point in a sealed tube was 63.5-65". Anal. Calc'd for C12H2&120&: C, 34.28; H, 6.68. Found: C , 34.92; H, 6.74. An attempt was made to prepare this compound by heating one equivalent of p-chloroethyl sulfoxide with three of thiodiglycol for six hours at 75". However, on cooling the oil which had formed, the original sulfoxide recrystallized. The mixture was completely soluble in chloroform, indicating that no salts had been formed. Osidation of the sulfonium salt ( X l l i ) with chloramine-T. T o 8.8 g. (0.022 mole) of the sulfonium salt in 50 ml. of water was added slowly with stirring 100 ml. of water containing 0.022 mole of chloramine-T. When about 30 ml. had been added a precipitate began t o form. After all the chloramine-T had been added, stirring was continued for one hour, The precipitate was removed by filtration and dried over calcium chloride. There was thus obtained 3.5 g. (92% yield) of crystals melting a t 123-124". Recrystallization from benzene and then from ethanol raised the melting point to 135-136". A mixture with an authentic sample of p-toluenesulfonamide (m.p. 133-134') melted at 133-134". The yield of crude amide indicated that no sulfilimine had been formed. Isolation of the sulfoxide of the sulfonium salt from the water solution was not attempted, since the properties of the compound made success seem unlikely. Preparation of the sulfonium salt sulfone (XVZ). A 20 g. (0.05 mole) sample of the sulfonium salt XIV was dissolved in a small amount of water and 17 g. (0.15 mole) of 30% hydrogen peroxide was added. The solution was evaporated in a stream of dry air until no further loss in weight occurred; the resulting oil was then dried in a vacuum desiccator containing phosphorus pentoxide a t a pressure of one millimeter until no further evolution of gas was observed and constant weight was attained. The liquid residue was completely insoluble in chloroform, showing; that decomposition of the sulfonium salt had not taken place. The oil was soluble only in methanol and water, was not hygroscopic, and did not crystallize on prolonged cooling in dry ice or liquid air accompanied by rubbing under various anhydrous solvents. Crystals of the sulfoxide of the sulfonium salt, instead of causing the oil t o crystallize, readily dissolved in it. -4solution of 5 ml. of water csontaining 1.5 g. of the oil was treated with a n excess of potassium mercuric iodide solution. -4heavy oil precipitated which was washed successively with potassium iodide solution, two portions of water, then ethanol. The residual oil was dried t o constant weight in uucuo over phosphorus pentoxide. There was thus obtained 3.2 g. of a honey-like oil, a 97% yield assuming the oil t o be
[
+ C HC~ H OH] ~ LHg-S CHz CH, -so2 CHnCH20Hj2
Attempted preparation of derivatives of the sulfone of the sulfonium salt by the addition of aqueous solutions of chloroplatinic acid, chlorauric acid, mercuric chloride, and picric acid to the sulfone led in every case to the formation of insoluble oils which did not crystallize.
245
REACTIONS OF MUSTARD GAS IN WATER
Preparation of &-(S,6-dinitrobenzoxy)ethyl sulfide and sulfoxide. A SOhtiOn of 1 g. of thiodiglycol was shaken with 4 g. of 3,5-dinitrobenzoyl chloride while 0.7 g. of sodium hydroxide in 10 ml. of water was added in small portions. The precipitate which formed was recrystallized several times from a mixture of ethanol and benzene. The melting point of the final product was 161-162". Anal. Calc'd for C1~H&rOl$: C, 42.35; H, 2.74. Found: C, 42.77; H, 2.97. The corresponding derivative of the sulfoxide was prepared by the same procedure. The material was recrystallized from butanol, m.p. 185-186". C, 41.07; H, 2.67; S, 6.08. Anal. Calc'd for Cl~H14K401,S: Found: C, 41.35; H, 2.79; S, 5.67. TABLE I1 DISTILLATION OF 6-CHLOROETHYL DISULFIDEFROM WATER-WASHED LEVINSTEIN MUSTARD WEIGHT IN G B W S
2.80 0.90 4.65 6.05 4.90 7.85 7.55 8.60 8.65 8.45 9.00 8.40 5.65 3.95 6.55 7.30 6.60 1.05
B.P., (2 MM.)
"c
41-57 57 61 60-65 65-87 91 92 91 92 92 90 89 91-95 94-98 101-106 105-118 106-I11 111
n"
1.5755 1.5769 1 .5365 1.5291 1.5352 1.5602 1.5657 1,5660 1.5659 1.5660 1,5659 1.5658 1.5659 1.5666 1.5673 1.5697 1.5688 1.5683
bis-8-Hydrozyethyl sulfone diacetate. The oil resulting from the oxidation of 10 g. of thiodiglycol with an excess of 30% hydrogen peroxide according t o Gilman and Beaber (7) was treated with an excess of acetic anhydride, added dropwise. A vigorous reaction occurred and the solution became slightly discolored. After evaporation of acetic acid, the oil was subjected to vacuum distillation in a Claisen flask. The fraction boiling a t 170190" (2 mm.) was redistilled twice through a small column and a fraction obtained boiling at 175" (2 mm.). I n distillation, small amounts of thioxane sulfone (m.p. 130") separated from the main fraction as a n immiscible oil which solidified on cooling. This was removed by filtration before redistillation and from the final product before analysis. Anal. Calc'd for C ~ H ~ , O BC, S : 40.33; H, 5.88; S, 13.57;Sap. eq., 119.1. Found: C, 39.90; H, 5.97; S, 13.28; Sap. eq., 121.4. It is interesting t o note that, in measurement of the saponification equivalent, the diacetate was saponified instantly by cold dilute aqueous alkali. This ease of saponification is analogous to the case of dehydrohalogenation of 8-chloroethyl sulfone by alkali. It also probably explains why all attempts to prepare the bis-3,5-dinitrobenzoate of the
246
C. C. PRICE AND 0. H. BULLITT, JFL.
sulfone (XIII) failed, since these attempts all involved either preparation in the presence of alkali or washing with alkali. Distillation of water-washed 1,evinstein mustard. An eleven-hundred-gram sample of Levinstein mustard was stirred in a 5-1. flask with fresh portions of water until the residue weighed 892 g. This was then d i d l l e d from a Claisen flask at reduced pressure. There was first distilled 620 g. (69.5%) of water-white, nearly odorless material boiling at 59" (1 mm.), n E 1.5281, having a refractive index close to that of pure 8-chloroethyl sulfide, n 1.5273 (1). The odor and color did not change on standing in glass exposed to light. Following this distillate there was obtained 163 g. of a yellow liquid boiling a t 59-120' (1-4 m.) and having a foul odor. Considerable decomposition occurred in the pot during this part of the distillation.
E
TABLE I11
DISTILL~ATION OF LEVINSTEIN MUSTARD WEIGHT PI G W S
I
B.P.,
228 204 89
"c
I
PRESSVBE IN U.
0.13 0.13 0.25-0.35 0.35-0.55 0.55-1.1
57 57 58-59
I
n:
1 .5273 1.5278 1.5287 1 .5308 1.5441
1
TABLE IV DISSOLUTION OF LEVINSTEIN MIJSTARD BY SHAKING WITH WATERAT ROOM TEMPERATURE
6.8 15 30
I
6o
1
1
294 285 270 240
0.102 ,195 .248 .285
1
I
(1.093 .192 .353 .45
0.096 .189 .371 .782
80.3 75.2 73.8 77.7
i
1 .o 2.8 5.8 12.0
85
I
3300 9600 43,200 48,000
The 163-g. sample was redistilled through a column packed with Berl saddles. The results, summarized in Table 11, indicate that 80 g. of the 110 g. distilled was fairly pure &chloroethyl disulfide (1). From the first two fractions taken, a small amount of solid separated on cooling. Two recrystallizations from ether gave 0.08 g. melting a t 110-111". Pure dithiane melts a t 112" (10).
Distillation of unwashed Levinstein mustard. Seven hundred seventy-five grams of Levinstein mustard was distilled a t reduced pressure from a one-liter Claisen flask. There was noticeable decomposition with the evolution of gases throughout the distillation, increasing as the bath temperature increased. The results are summarized in Table 111. The distillate was all yellow-brown, with the higher-boiling fractions somewhat darker than the others. The odor of each fraction was a mixture of 8-chloroethyl sulfide and hydrogen chloride. Significantly, there was no foul odor in the last fraction corresponding to that found in distillates from water-washed Levinstein mustard. Persistence of Levinstein mustard in water. Four mixtures of water and Levinstein mustard in glass-stoppered Erlenmeyer flasks were placed on a shaking machine. Two cubic centimeter samples of water were withdrawn periodically and the chloride ion titrated
247
REACTIONS OF MUSTARD GAS IN WATER
by the Volhard method. A t the end of the experiment, the volume of insoluble black oil ( n z 1.74) was measured. The results are tabulated below (Table IV). Assuming 6chloroethyl sulfide (I) to be the only substance reacting and dissolving, the per cent of I in the Levinstein was calculated both from the chloride ion liberated and from the volume of the insoluble residue. Results of potassium mercuric iodide tests for the amount of sulfonium salt XIV formed are also included in the table. The reaction of 8-chloroethyl di-, tri-, and penta-sulfides with aqueous chloramine-T. Dioxane was added to 0.185 g. (0.968 millimole) of 8-chloroethyl disulfide (l),0.138 g. (0.618 millimole) of 8-chloroethyl trisulfide (I), and 0.132 g . (0.460 millimole) of 8-chloroethyl pentasulfide (1)to make 50.0 ml. of solution in each case. Each standard solution was TABLE V CHLORINEDEMAND OF 8-CRLOROETHYL DISULFIDE, TRISULFIDE, AND PENTASULFIDE TIMEINMINUTES
1
MOLES
x 10-
CEL.-T CONSUKED
1
MOLE-PATIO OP W . - T TO SULFIDE
15 35 55 95
0.368 .458 .483 .503
3.8 4.7 5.0 5.2
10 25 35
70
0.421 .477 .488 .491 .497
6.8 7.7 7.9 7.9 8.0
10 15 30 45 70
0.557 .586 .619 .626 .632
12.1 12.7 13.4 13.6 13.7
50
used in turn in the following procedure. To 100 ml. of 0.034 N aqueous chloramine-T solution was added 5.0 ml. of the standard dioxane solution. After 30 seconds, 5 ml. of concentrated hydrochloric acid was added. At the end of a known time interval, an excess of solid potassium iodide was added and the liberated iodine titrated with 0.0224 N sodium thiosulfate. The amount of chloramine-T consumed was then calculated. The results are summarized in Table V. SUMMARY
An investigation of the hydrolysis and oxidation of @-chloroethylsulfide, undertaken to evaluate its hazards as a water contaminant, has established a number of hydrolytic and oxidative transformations in aqueous solution. UBBM-A,ILL.
248
C. C. PRICE AND 0 . H. BULLITT, JR.
REFERENCES FUSON et ul.,J. Org. Chem., 11,469 (1946). HELFERICR AND REID,J . A m . Chem. SOC., 42, 1208 (1920). MANNAND POPE,J . Chem. SOC.,121, 1052 (1922). AND WAL(a) MARSHALL AND WILLIA-MS, J . Phurmacol., 16, 268 (1920). (b) PETERS KER, Biochem. J . , 17, 260 (1923). (5) LEWIN,J . prukt. Chem., (2), 127,77 (1930). (6) KRETOW, J . Russ. P h y s X h e m . Soc., 62, 1 (1930). (7) GILMANAND BEABER, J . A m . Chem. SOC.,47, 1451 (1925). (8) BAUMAN AND WALTHER, Bcr., 26, 1124 (1893). (9) DAVIES AND OXFORD,J. Chem. SOC.,229 (1931). (10) MANSFELD, Ber., 19, 700 (1586). (1) (2) (3) (4)
