1168
ANALYTICAL CHEMISTRY
the approximate density. If isobutylene is present it is advisable to add a few grams of o-cresol to inhibit the polymerization of isobutylene which makes the subsequent ether stripping operation difficult. The sample is then saturated with boron trifluoride until a white cloud of hydrolyzed boron trifluoride appears in the vent' gases, indicating complete reaction of the ether. The unreacted methyl chloride is allowed to boil off by slowly warming the reaction flask while passing a small stream of pure methyl chloride through it. This vaporization should require about 20 minutes. When vaporization is completed the system is flushed out with pure methyl chloride and the reflux headiscooledto about -70' F. with dry ice and acetone while flushing with methyl chloride is cont,inued. When 10 to 12 ml. of methyl chloride have collected in the graduated receiver, 100 ml. of 10% sodium hydroxide are added dropwise to the reaction flask. The caustic solution is then stripped with a stream of methyl chloride until 20 to 25 ml. of methyl chloride have collected in the receiver. The concentrated sample is then transferred to a small evacuated bomb in which it may be held unt,il ready for the infrared determination of the ether content. ACCURACY AND PRECISION
By concentrating the sample in the nianner described, the minimum detectable amount has been reduced to about 5 p.p.m. (depending on the degree of concentration), and the precision increased to the same figure (Table 111). For the infrared method alonP the minimum detectable is at, best 0.007$70 with a maximum
precision of +0.004%. The precision here stated is true only when the concentration of the ether is in the range studied in this investigation, which was below 0.1%. ACKNOWLEDGMENT
The authors wish to acknowledge the assistance of members of the Esso Laboratories, Chemical Division, Standard Oil Development Company; of the Chemical Products Laboratory, Louisiana Division of Esso Standard Oil Company; and of K. J. SYhittrt, formerly of this laboratory. LITEKATL'KE CITED (1) Bamea, H. B., Liddel, V., and TVilliains, 1'. Z . , IND. Exo. h r a ~ ED., . 15, 659-709 (1943).
(:HEY.,
(2) Bennett and M e j w , Phus. Rev., 32, 888-905 (1928). (3) Brattain, R. R., and Beeck, 0, J . , A p p l i e d Phus., 13, fi9!1--71)5
(November 1942). (4) Brown and Adams, J . A m . Chena. Soc., 64, 2557 (1942). (5) Clairhorne, E. B., unpublished data. (6) Crawford and Joyce, J . Chem. P h y ~ . 7, , 307-10 (1939). (7) Hodgman. C. D., "Handbook of Cheniistry and Physicb," 28th ed., Cleveland, Ohio, Cheniical Rubber Publishing Co., 1944. (X) Maah and McIntosh, J . Am. Chem. Soc., 34, 1274 (1912). Kt:ruv?:ii December 17. 1048.
Infrared Spectra of Sulfones and Related Compounds JCC'HII' C. SCHKEIRER. Columbia C'nioersity$ Vew York,.V. Y .
I
S THE past decade the identification of structural features oi organic molecules by means of infrared absorption spectra has been the subject of a large number of systematic invrstigations in which the absorption characteristics of many functional groups have been established. I n the field of oigariic sulfur compounds, investigations of mercaptans (thiols), sulfides, and disulfides have established a sulfur-hydrogen stretching vibration ( 5 , 6, 18, 44) in the region of 2500 em.-', a carbon-sulfur stretching vibration (43) between 600 and 700 an.-!, and finally a sulfur-sulfur stretching vibration (43) in the neighborhood of 500 em.-' Among inorganic sulfur compounds, sulfur dioxide (31) s h o w bands at 1151 and 1361 cm -l, respectively, which represent sulfur-oxygen stretcahing frequencies, tvhile suli'ur trioxide (21) shows three bands a t 1065,1205, and 1330 cm. Duval and Lccomte (16, 17) have reported that inorganic dithionates absorb a t approximately 985 and 1200 em.-' No systematic investigation of sulfur-oxygen absorption frequencies in organic moleculrs has been reported. Data on only a few isolated compounds have been published. Downing et aE. (16)have investigated the spectra of bis-(p-chloropheny1)-sulfone and of 2,2,2-trichloro- 1-(0-chloropheny1)-ethyl-p-chlorobenzenesulfonate in connection with the analytical determination of D D T in industrial manufacture. Barnes et al. (3)have recorded curves for orthanilic, metanilic, and sulfanilic acids, and O-, m-, and p-sulfanilamide. Adanis and Tjepkema ( 1 ) have reported the spectra '-disubstituted-.~,-~-'-dibeneenesulfonyldiaminoof sixteen mesitylenes and stated that they show an absorption between 1160 and 1180 cm.-' due to the -SO*group. Barnes et al. (2) in a table of functional group absorption frequencies have tentatively assigned the region of 1290 to 1350 cm.-l to sulfone absorption and the region of 1140 to 1200 cm.-' to the absorption of thc sulfonate grouping. But no experimental data are pre5ented in their paper.
This investigation was undertaken in aider to obtain experimental ditta on the sulfur-oxygc.11 stretching frequencies in sulfones and related compounds; 110 attrbinpt was made to obtain a
Table I.
Absorptions of Sulfones and Sulfides between 1100 and 1400 Cm:
Diyhenylsulf one 1110 Diphenylsulfide (23) Di-n-butylsulfone (16) Di-n-britylsuifide (8) ~lethj.letliylsulfone (4) .Uethylethylsulfide (27, 18) Phenylbenzylsulfone ( 5 7 ) 1128 Phenylbenzylsulfidr Dibenzylsulfone 1120 Dibenzylsulfide (30) Di-(n-butylsulfonyl)rnpthane (LO) Di-(n-hutylmercanto)-methane
[%I
1135 1139 114.5 1155 1133
1148 1150 1140 102
1310" 1325 1305 1330 1330
1340
1238 1221 1170" 1202 1201 1184 1225 1302 1175 1229 126j4 1258
1345 1325 1318
1153
1180
1225
1286
1313
1130
1171 1170 11,57
1220 1229 1220
1280 1285 1285
1315
1240
1293
1321,
1235
1295" 1301 1330
1ox
1128 1150
1380 1383
1305" 1325 1300 1326
1130
141'' 1159
Phknylallylsulfone Phenylallylsulfide Met hylvinylsulfone JIethyl\ inylsulfide Bis-(p-hydroxyuhenv1)sulfone Bis-(p-hydroxypheny1)sulfide Thiodiglycolsulfone Thiodiglycol Thiodiglycol diacetatesulfone Thiodiglycol diacep-Tolylallylsulfone tate
1166'' 1166 1175 1 1 7 j 1230 1280 1259 1258 1242 1203 1270 1200 1245
1183
Tri-(ethylsulfony1)1134 1158 117.ja 1231 methane Ethyl+-(phenylsul1115 1153 1177 1275 fony1)-acetate a Well defined knee in curve at point indicated.
1387 1390
1300a 1352 1350
1, 3 8 0
V O L U M E 21, NO. 10, O C T O B E R 1949
1169
The infrared spectra in the region 1000 to 1500 cm.-' of thionyl chloride, sulfuryl chloride, sixteen sulfones, thirteen sulfides, two sulfoxides, two sulfates, two sulfonates, three sulfonic acids, three sulfonamides, and one sulfonyl chloride are reported. Characteristic bands for the -SOzgroup are discussed.
cotiditions used, whereas a value of 8 t o 11 mi.-' would have beer1 wlfur-oxygcn imiding frequc~ncy. ('onsideri~igthe data i i i tlie rspected from the data given in the manual supplied a i t h the above-mentioned papr'rs (n-ith the exception of that by Adarm, I spectrometer. -4pprosimately the latter resolving po\vr'r i which was published whilc this work \vas in progress), as ~ ~ a:: 1 1 urhieved with Halford's instrument in these laboratories, nhic~h. the Raniaii sp&runi of sulfuryl chloride ( I f ,SO, 54)which . ~ h o \ v s however, was not available for the work reported here. All specti,;%m r e taken using a sodium chloride prism. The sample frcquency diifts of 1182 and 1408 c m - ' , it wa.~decided t o irivesticell employed consisted of rock-salt plates sep:ir:ited by a lead gate carvfully then rvgion Ironi 1000 t o 1500 rtn. -1 gasket of 0.101-mm. thickness (12). ,111 spectra were taken in solution. The sulvcmis are indicateti with each curve (Figures 1 to 6 ) and were commercial solvent.; :E XP E:KI11m ' r A L that' were dried and fractionated through a glass helix fractionating column prior to use. The concentrations ranged from 30 t o Instrument Used. The work described in this paper was performed using a Perkin-IClnier Model 12B infrared spectrometer 100 mg. of coinpound per cubic centimeter of solvent. The molar with a breaker-type amplifier arid a Brown strip-chart, electronic concentrations of corresponding sulfides and sulfones were the recorder. The instrunient was used in the state of adjustment as same, so that the extinctions are directly comparable. The final curves were obtained on a point by point basis from the ink supplied hy the nianufacturer. It was found that its resolving power \vas 20 t o 25 lracings of tlie transmittmres of the solution and of the solvent,. between 1000 arid 1400 em.-' tinder the ~
10
WAVE LENGTH, MICRONS 8
9
WAVE LENGTH, MICRONS 9 8
10
7
80
60
B
U W
f
40
I-
C PO
H
< E I-
t 80 U
6 60 a 40
PO
PO /
10.0
.
1100
.
.
.
I
.
.
.
I
.
1900 1300 WAVE NUMBERS, CM.-1
.
'
.
1400
40 ,
.
I
1500
Figure 1 . Infrared Spectra of Sulfones and Sulfides .4.
B.
C.
D.
Diphenylaulfone in chloroform and acetonitrile - - - Diphenylsulfide i n carbon tetrachloride i n carbon tetrachloride - - - Di-n-butylsulfone Di-n-butylsulfide in carbon tetrachloride Methylethylsulfone in acetonitrile - - - Methylethylsulfide in carbon tetrachloride in carbon tetrachloride - - - Phenylbenzylsulfone Phenylbenzylsulfide in carbon tetrachloride
t
L . 1000
Figure 2. -4.
n. C.
D.
V
.
I
.
1100
.
I
1 PO0 1300 WAVE NUMBERS, CM.-1
, . . . . 1400
1500
Infrared Spectra of Sulfones and Sulfides
7 Dibenzylsulfone
in acetonitrile
- - - Dibenzylsulfide in carbon tetrachloride in carbon tetrachloride --- - Di-(n-butylsulfonyl)-methane Di-(n-bnty1mercapto)-methane in carbon tetrachloride 1,2-Di-(phenylsulfonyl)-ethane in acetonitrile - - - 1 2-Di-(pheny1mercapto)-ethanein acetonitrile in carbon tetrachloride - - - diphenyldisulfone Diphenyldieulfide in carbon tetrachloride
1170
ANALYTICAL CHEMISTRY WAVE LENGTH, MICRONS
WAVE LENGTH, MICRONS
a
9
10
7
a
9
10
1
I
E
1
60
Y
$ 40
5
PO
f 5 IC
5 80
U
$ 60 P
40
PO
80
60 40
Po
t I
W "
'
.
1000
'
,
.
1100
.
.
.
I
1PO0
,
1I
I
1300
I400
1500
PO IPO0 1300 WAVE NUMBERS, CM.-1
1000
1100
WAVE NUMBERS, CM. -1
Figure 3. A. E.
C. D.
---
Infrared Spectra of Sulfones and Sulfides
Phenylallylsulfone in carbon tetrachloride Phenylallylsulfide in carbon tetrachloride Mcthylvinylsulfone in carbon tetrachloride Mcthylvin>lsulfidein carbon tetrachloride Bis-(p-hydroxyphenyl)-sulfone i n acetonitrile Bis-(p-hydroxyphenyl)-sulfidein acetonitrile Thiodiglycolsulfonc in acetonitrile Thiodiglycol in acetonitrile
--------
The methods of preparation of the compounds are indicated by literature references in the tables. Diphenylsulfone, benxenesulfonic acid, p-toluenesulfonic acid, benxenesulfonyl chloride, the sulfonamides, and the sulfonates were obtained from the Eastman Ilodak Company. DISCUSSION OF RESULTS
The spectra of thirteen sulfones and of the corresponding sulfides have been examined for bands characteristic of the sulfone grouping. Each of the sulfones shows two which are absent in the corresponding sulfides. These absorptions occur beta-een 1120 and 11GO cm.-' and between 1300 and 1350 cm.-l (see Table I). Both are strong absorptions, the one a t the longer wave length (8.6 to 8.9 microns or 1120 to 1160 cm.-I) usually being slightly stronger. No sulfides have been investigated which have absorptions in these regions due to absorptions of other parts of the molecule, such as naphthyl and metasubstituted phenyl sulfides, because the bands in the corresponding sulfones would be either unresolved or difficult to interpret. Throughout this work the difficulty of finding a satisfactory solvent was encountered. Although carbon tetrachloride is excellent because it has only weak absorptions in the region investigated, many of the sulfones and of the compounds discussed below
Figure 4. A.
1400
1500
Infrared Spectra of Sulfones and Sulfides
---
Thiodiglycol diacetatcsulfone in acetonitrile Thiodiglycol diacetate in carbon tetrachloride B . p-Tolglallylsulfone in carbon tetrachloride C. Tri-(cthylsulfony1)-methane in acetonitrile D. Ethyl-,9-(phenylsulfonyl)-acetatein acetonitrile
are not sufficiently soluble in this solvent. Chloroforni can be used, but it has an absorption band a t 1216 cm. -1 which obliterates the region between the two frequencies in question. Acetonitrile, a solvent in which most of the investigated compounds are sufficiently soluble, unfortunately has two strong absorptions at 1040 and 1420 cm.-l The second absorption is so strong, that, with the cell used, any pattern of the solute above 3350 cm.-' is masked.
Table 11. lbsorption of Compounds Containing -SO? Group Benzenesulfonamide o-Toluenesulfonamide p-Toluenesulfonamide Methyl p-toluenesulfonate n-Butyl p-tolaenesulfonate Benzenesulfonic acid Ethanesulfonic acid p-Toluenesulfonic acid Benzenesulfonyl chloride Dimethylsulfate Diethylsulfate Sulfuryl chloride
1100 1140 1100 1100 1100 1100
1167 130la 1162 1285 1167 1300 1185 1198 1315 1185 1198 1315 1182 1261 1171 1242 1300 1100 1170 1250 1300 11211 1185 1195 1322 1193 1161 1187 1128 1160 1196
Well defined knee in curve at point indicated.
1358 1346 1358 1375 1370
1340 1390 1412 1415 1419
1171
V O L U M E 2 1 , NO. 1 0 , O C T O B E R 1 9 4 9 I t is therefore hard to interpret the spectrum of a compound in the region of the second absorption of the sulfone grouping. W A V E LENGTH, MICRONS 10
9
1
8
80
A number of other compounds, which are not sulfones but contain the -SOL - grouping, have bcen investigated, and their absorption is shown in Tablc 11. T h r band a t 1370 cm.-' in thv spectra of the sulfonates is a broad band stretching over about 20 em.-', and may be a doublet unresolved by the instrument. S o second absorption was observed in the spectra of sulfonic acids up to 1335 cm.-l, above which the absorption of the acc~toiiitrilernadc it impossible to draw any conclusions. The pcaks in sulfuryl chloride correspond to the Ranian shifts (11, 31, 43) which are to be expected, as this molecule b,.longs to the point group C J ,in which these absorptions are both infrared arid Ranian active. I n Tablc I11 the absorptions of threc compounds containing only one sulfur-oxygen bond are collectrd All compounds containing the --SO>-- grouping have an absorption in the region betnclen 1120 and 1300 c1i1.-~ This region can be tentatively divickd into two parts. Thc first, extending from 1120 to 1160 riii.-*, is characteristic ot sulfones. The second, coniprii;lng the range from 1160 to 1200 cm.-l, is characteristic of sulfonic acids, sulfuric acids, and their dcrivatives. The sccond absorption area between 1300 and 1400 em.-' is somewhat more in doubt. Sulfones definitc,ly have an absorpThe absorption tion in the region between 1300 and 1350 rni of sulfonic acid derivatives in the region 1330 to 1400 cm.-l will have to hc investigated further bsxfore they can be definitely as-
60
b
Z 40
Table 111. Absorption of Compounds Containing One Sulfur-Oxygen Bond
4
=i PO
zz
3 1
I
I-
Thionyl chloride Diphenylsulfoxide Di-n-hutylsulfoxide a
1140 1166'
(133
1238
12OOa 1183 1190
(22)
1350 1308
Well defined knee in curve at point indicated.
W A V E LENGTH, MICRONS 9
10
v ,
I
.
.
,"I
,
,
I
60
PO 40
1
t
\
/
A
P
L
1 '
. . .
1000
Figure 5.
-- -- ----- - ..
l
1100
.
,
.
.
I
1PO0
I
,
.
.
1
. . . .
1300 W A V E NUMBERS, CM. -1
1 : .
1400
. I 1500
Infrared Spectra of Compounds Containing -SOGroup
Benzenesulfonamide in acetonitrile o-Toluenesulfonamide in acetonitrile p-Toluenesulfonamide in acetonitrile Methyl p-toluenesulfonate in carbon tetrachloride B. n-Butyl p-toluenesulfonate in carbon tetrachloride C. Ethanesulfonic acid i n acetonitrile Benzenesulfonic acid in acetonitrile p-Toluenesulfonic acid in acetonitrile D . Benzenesulfonyl chloride in carbon tetrachloride E. Dimethylsulfate in carbon tetrachloride Diethylsulfate in carbon tetrachloride F. Sulfuryl chloride in carbon tetrachloride
A.
---
---
1
8
. .
.
I
.
(
.
. .
,
.
.
I
I
.
.
.
.
.
,
_ I
,
,
,
.
,
.
.
.
.
80
60
PO 40
I
I
1000
Figure 6.
1100
1200 1300 W A V E NUMBERS, C M . - '
1400
1500
Infrared Spectra of Compounds Containing One Sulfur-Oxygen Bond
A . Thionyl chloride in carbon tetrachloride B . Diphenylsulfoxide in carbon tetrachloride C. Di-n-butylsulfoxide in carhon tetrachloride
1172
ANALYTICAL CHEMISTRY
signed to the absorption of the sulfonyl grouping. The disubstit u k d sulfonamides investigated by Adams and Tjepkema ( 1 ) show in addition to the absorption reported by them, a band between 1330 and 1350 cm.-l which corresponds to the second absorption band of the sulfonyl group. The absorption between 1410 and 1420 c m . - ~of the sulfates and the single band of the sulfoxides at 1190 cm.-l need further confirmation. ACKNOWLEDGMENT
The author wishes t o express his appreciation and thanks to Ralph S. Halford, T. Ivan-Taylor, a i d William E. Doering for their helpful advice and guidance during both the experimental work and the preparation of this paper. LITERATURE CITED
Adams and Tjepkema, J . Am. Chem. Soc., 70, 4204 (1948). Barnes, Gore, Stafford, and Williams, ANAL.CHEM.,20, 402 (1948).
Barnes, Liddel, and Williams, IND.ENG.CHEM..i i x . i L . ED., 15, 659 (1943).
Beckman, J . prakt. Chem. (2). 17, 455 (1878). Bell, Ber., 60B, 1749 (1927). Ibid., 61B, 1918 (1928). Bell and Bennett, J . Chem. SOC.,1928, 3190. Bost and Conn, Org. Syntheses, Coll. Vol. 11, 547 (1943). Brown and Moggridge, J. Chem. Soc., 1946, 816. Buckley et al., Ibid., 1947, 1514. Cabannes and Rousset, Ann. phys., 19, 229 (1933) Coggeshall, Rev. Sci. Instruments, 17, 343 (1946). Colby and McLoughlin, Ber., 20, 195 (1897).
(14) Doering and Levy, unpublished results. (15) DonyI1ing, Freed, Walker, and Patterson, IND. ENG. &EM., ANAL.ED.,18, 464 (1946). (16) Duval and Lecomte, Bull. sot. chim. France, 11, 376 (1944) (17) Duval and Lecomte, Compt. Tend., 217, 42 (1943). (18) Ellis, J . Am. Chem. SOC.,50, 2113 (1928). (19) Friedel and Crafts, Ann. chim. (6), 14, 438 (1888). (20) Fromm and de Seixas Palma, Ber., 39, 3319 (1906). (21) Gerding and Lecomte, Physics, 6, 737 (1939), (22) Grabowsky, Ann., 175, 350 (1875). (23) Hartman, Smith, and Dickey, Org. Syntheses, Coll. Vol. 11, 242 (1943). (24) Hilditch, J . Chem. Soc., 93, 1526 (1908). (27) (28) (29) (30) (31) (32) (33) (34) (35) (36) (37) (38) (39) (40) (41) (42) (43) (44)
~~~~~; ~ ~ ; ~ ‘ ; r ~ l ~
sot., 52, 3356 (1930). ~ lJ , pTakt. ~ chlm, ~ (2), 15, ~ 174 (1878). ~ , Krueaer, I b i d . 12). 14. 206 (18761. Le&, I b i d . (2j, 127, 77 (1930).’ Matossi and Aderhold, Z . Phys., 68, 690 (1931). Mecke, Z. physik. Chem., B16, 409, 421; 17, 1 (1932). Michael and Comey, Am. Chem. , J . , 5, 116 (1883). Newman, J . Am. Chem. SOC.,68, ?712 (1946). Nisi, Japan. J . Phys., 6, 1 (1930). Otto, Ann., 283, 184 (1894). Otto, Be?., 13, 1280 (1879). Otto and Otto, Ibid., 21, 1696 (1888). Pummerer, I b i d . , 43, 1406 (1910). Shriner, Stutr, and Jorrison, J . Am. Chem. Soc.. 52, 2060 (1929) Stutr and Shriner, Ibid., 55, 1243 (1933). Tassinari, Gazz. chim. itaL., 17, 83 (1886). Ibid., 20, 362 (1890).
Trotter and Thompson, J . Chem. SOC.,1946, 481. Williams, Phys. Rev. (2), 54, 504 (1938).
RECEIVED January 21, 1949.
Punched Card Code for X-Ray Diffraction Powder Data F. W. IIL.i’ITHEWS, Canadian Industries Limited, .McMasteruille, Quebec, Canada A punched card is described which would enable a rapid and exhaustive search to be made of powder x-ray diffraction data for the identification of crystalline chemical compounds. This search could be based on the most intense lines of the x-ray diffraction pattern or on one intense line of the diffraction pattern and the elemental chemical composition of the substance.
T
HE identification of a chemical compound by the use of x-ra\‘
diffraction powder patterns is based on a thesis of Hull (6) “that every crvqtalline substance gives a diffraction pattern; and that the same substance alwaj s gives the same pattern.” It remained to be shown by Hananalt and Rinn ( 6 ) that these patterns 17 ere sufficiently different to become the basis of a practicd method of analysis. These authors described a method of tabulating powder patterns in a manner suitable for routine chemical identification, This scheme used a large ledger which \vas unsuitable for reproduction and general distribution 4s an alternative, a card file of thew data, using basicall) the same scheme, was published by the American Society for Testing Alaterials ( I ) . This provides an expandable file which is suitable for indexing a comparatively small number of data. The present file, which lists about 4000 substances, has already proved somewhat unwieldy. If data on three times this number of substances \\ere considered. the size of the file m-ould be such that a search would be very difficult. Alternative solutions to this problem, including the use of punched cards, were discussed in a previous paper (7). The present paper presents a revised punched card code which would facilitate the search of a file of powder diffraction data.
The method of Hanaualt and Rinn (6) used the three most intense (strongest) lines of the powder diffraction pattern as the index lines. The use of three lines is required because variations in x-ray technique and texture of the sample of a given substance cause variations in the relative intensities of the lines of the diffraction pattern. I n the ten years this method has b e m in general use, the use of three index lines has proved necesqary and effective for searching purposes. I n searching a file of data for the identification of a poivder diffraction pattern, it is usual t o start v i t h two diffraction lines of the pattern. Ideally these would be the strongest and second strongest lines of the pattern, but because of the variation in relative intensity of the lines, and the danger that strong lines may be missed in the case of mixtures, an index to be used for an exhaustive search should list the six combinations of the three strongest lines. The card file of diffraction data published by the h.S.T.M provided three cards for each entry, placed in the index in positions determined by three combinations of the strongest lines-lst, 2nd; 2nd, 1st; 3rd, 1st. The combination lst, 3rd, which has a relatively high probability of occurrence, and the two combinations 2nd, 3rd and 3rd, 2nd, which become important if the first line were missed, would have required three more cards in
