Synthesis and mass spectral studies of some (E)- and (Z)-1-alkylthio - and 1-alkylsulphonyl-2-P-tolylsulphonylstilbenes

Article abstract of DOI:10.1080/10426500701372157

A number of (E)- and (Z)-1-alkylthio-2-p-tolylsulphonylstilbenes (3a-i and 5a-i) were synthesized by the nucleophilic displacement of halogens with sodium salts of various alkanethiols on (E)-1-chloro-2-p-tolylsulphonylstilbene (1) and (Z)-1-bromo-2-p-tol

Full text of DOI:10.1080/10426500701372157

This article was downloaded by: [McMaster University]
On: 23 December 2014, At: 02:59
Publisher: Taylor & Francis
Informa Ltd Registered in England and Wales Registered Number: 1072954
Registered office: Mortimer House, 37-41 Mortimer Street, London W1T 3JH,
UK
Phosphorus, Sulfur, and Silicon
and the Related Elements
Publication details, including instructions for
authors and subscription information:
http://www.tandfonline.com/loi/gpss20
Synthesis and Mass Spectral
Studies of Some (E)- and
(Z)-1-Alkylthio - and
1-Alkylsulphonyl-2-P-
Tolylsulphonylstilbenes
Mahammed Shafi a , Manzoor Hussain a & S. Ghouse
Peeran a
a Department of Chemistry , Sri Krishnadevaraya
University , Anantapur, India
Published online: 16 Jul 2007.
To cite this article: Mahammed Shafi , Manzoor Hussain & S. Ghouse Peeran (2007)
Synthesis and Mass Spectral Studies of Some (E)- and (Z)-1-Alkylthio - and 1-
Alkylsulphonyl-2-P-Tolylsulphonylstilbenes, Phosphorus, Sulfur, and Silicon and the
Related Elements, 182:9, 2087-2103, DOI: 10.1080/10426500701372157
To link to this article: http://dx.doi.org/10.1080/10426500701372157
PLEASE SCROLL DOWN FOR ARTICLE
Taylor & Francis makes every effort to ensure the accuracy of all the
information (the “Content”) contained in the publications on our platform.
However, Taylor & Francis, our agents, and our licensors make no
representations or warranties whatsoever as to the accuracy, completeness,
or suitability for any purpose of the Content. Any opinions and views
expressed in this publication are the opinions and views of the authors, and
are not the views of or endorsed by Taylor & Francis. The accuracy of the
Content should not be relied upon and should be independently verified with
primary sources of information. Taylor and Francis shall not be liable for any

losses, actions, claims, proceedings, demands, costs, expenses, damages,
and other liabilities whatsoever or howsoever caused arising directly or
indirectly in connection with, in relation to or arising out of the use of the
Content.
This article may be used for research, teaching, and private study purposes.
Any substantial or systematic reproduction, redistribution, reselling, loan,
sub-licensing, systematic supply, or distribution in any form to anyone is
expressly forbidden. Terms & Conditions of access and use can be found at
http://www.tandfonline.com/page/terms-and-conditions

Phosphorus, Sulfur, and Silicon, 182:2087–2103, 2007
Copyright © Taylor & Francis Group, LLC
ISSN: 1042-6507 print / 1563-5325 online
DOI: 10.1080/10426500701372157
Synthesis and Mass Spectral Studies of Some
(E)- and (Z)-1-Alkylthio - and
1-Alkylsulphonyl-2-P-Tolylsulphonylstilbenes
Mahammed Shafi
Manzoor Hussain
S. Ghouse Peeran
Department of Chemistry, Sri Krishnadevaraya University, Anantapur,
India
A number of (E)- and (Z)-1-alkylthio-2-p-tolylsulphonylstilbenes (3a–i and 5a–i)
were synthesized by the nucleophilic displacement of halogens with sodium salts
of various alkanethiols on (E)-1-chloro-2-p-tolylsulphonylstilbene (1) and (Z)-1-
bromo-2-p-tolylsulphonylstilbene (2) respectively. Oxidation of these (E) - and (Z)-1-
alkylthio-2-p-tolylsulphonyl gave the corresponding (E)- and (Z)-1-alkylsulphonyl-
2-p-tolylsulphonylstilbenes (4a–i and 6a–i) respectively. Mass spectral data of all
the synthesized compounds were examined. Smiles-type rearrangement observed
in (E)-and (Z)- sulphide-sulphones (3a–i and 5a–i) was absent in (E)- and (Z)-
disulphones (4a–i and 6a–i). Loss of sulphur dioxide and sulphonyl-sulphinate
rearrangement with vinyl migration was noticed in all the synthesized compounds.
McLafferty-type rearrangement was observed only in (E)- sulphide-sulphones and
(E)- disulphones but not in the corresponding (Z)-isomers.
Keywords (E)-1-Alkylthio-2-p-tolylsulphonylstilbenes; (E)-1-alkylsulphonyl-2-p-toly-
lsulphonylstilbenes; (Z)-1-alkylthio-2-p-tolylsulphonylstilbenes; (Z)-1-alkylsulphonyl-2-
p-tolylsulphonylstilbenes
INTRODUCTION
Biological studies carried out on vinylsulphonyl compounds1 and bis
(organosulphonyl)ethylenes2,3 revealed that they can be used as ef-
fective fungicides to protect seeds. Although some reports4−8 have
appeared on the synthesis of cis- and trans-sulphide-sulphones and
disulphones, the mass spectral data available on these compounds
is scanty. In order to study the effect of geometry of double bonds
Received January 9 2007; accepted March 14, 2007.
It gives the authors great pleasure to acknowledge the authorities of IICT, Hyderabad,
A.P. India, for mass spectral recordings.
Address correspondence to S. Ghouse Peeran, Department of Chemistry, Sri Krish-
nadevaraya University, Anantapur 515003, India. E.mail : sgpeeran@gmail.com
2087

2088
M. Shafi
upon fragmentation path ways, we have under taken the syn-
thesis and mass spectral studies of some (E)- and (Z)-1-alkythio
- 2-p-tolylsulphonylstilbenes (3a–i and 5a–i) and (E)- and (Z)-1-
alkylsulphonyl-2-p-tolylsulphonylstilbenes (4a–i and 6a–i).
DISCUSSION
When (E)-1-chloro-2-p-tolylsulphonylstilbene (1) was treated with
sodium salts of various alkanethiols, nucleophilic displacement
of chlorine took place with retention of configuration5,9,10and
gave (E)-1-alkylthio-2-p-tolylsulphonylstilbenes (3a–i) (Scheme1).
Compounds 3a–i on oxidation with hydrogen peroxide afforded (E)-1-
alkylsulphonyl-2-p-tolylsulphonylstilbenes (4a–i). Similarly when (Z)-
1-bromo-2-p-tolylsulphonylstilbene (2) was treated with sodium salts of
SCHEME 1

Trichlorosilane Reduction of Phosphine Oxides
2089
TABLE I The m/z Values and Intensities of the M+. Peaks of (E)-and
(Z)-P-CH3C6H4SO2(C6H5) C C (C6H5)SR
M+.
R
(E) m/z (rel. int. % )
(Z) m/z (rel. int. % )
CH3
CH3 CH2
380(37)
394(26)
408(38)
408(36)
422(32)
422(28)
422(26)
436(24)
436(25)
380(29)
394(20)
408(25)
408(18)
422(20)
422(16)
422(10)
436(14)
436(16)
CH3(CH2)2
(CH3)2CH
CH3(CH2)3
(CH3)2CH CH2
(CH3)3C
CH3(CH2)4
(CH3)2CH(CH2)2
various alkanethiols, nucleophilic displacement of bromine occured re-
sulting in the formation of (Z)-1-alkylthio-2-p-tolylsulphonylstilbenes
(5a–i) with retention of configuration5,6 (Scheme 1). Oxidation
of 5a–i with hydrogen peroxide afforded (Z)-1-alkylsulphonyl-2-p-
tolylsulphonylstilbenes (6a–i). The mass spectral features of (E)- and
(Z)-1-alkylthio-2−p-tolylsulphonylstilbenes (3a–i and 5a–i) and their
corresponding disulphones (4a–i and 6a–i) were examined at 70 eV.
Molecular ion peaks were observed in all the (E)- and (Z)-sulphide-
sulphones, however the molecular ion peaks of the (E) -isomers (3a–
i) were more intense than their corresponding (Z)-isomers (5a-i), Ta-
ble I. A peak at m/z value 333 was observed in the mass spectra of
all the (E)- and (Z)-isomers and is believed to be produced by the loss
of RS. from the molecular ions (Scheme 2). The base peaks were ob-
served either at m/z 178 or at m/z 210. The 178 peak is assigned to
diphenylacetylene radical cation and the 210 peak to a cyclic sulphe-
nium cation (Scheme 3). Smiles-type rearrangement leading to the for-
mation of alkyl p-tolylsulphide radical cations (p-CH3C6H4SR+) (I) was
noticed11 in all the (E)- and (Z)-sulphide-sulphones. The proposed re-
arrangement mechanism (Scheme 3), involves initial ionisation of the
sulphide which permits the rotation of trans- into cis-geometry, which is
a prerequisite for such a rearrangement and hence was observed in (E)-
isomers also. The molecular ions also underwent fragmentation by the
loss of p-CH3C6H4SO.2forming a cation (II) whose proposed structure is
shown in Scheme 4. An intense peak at m/z 211 was observed in all the
sulphide-sulphones except in 3a and 5a which may be formed from the
cation II by the loss of an olefin, where in the transfer of β-hydrogen
from the alkyl group to the sulphur atom followed by cleavage of C S

2090

2091

2092

Trichlorosilane Reduction of Phosphine Oxides
2093
bond occurs. The absence of 211 peak in 3a and 5a may be explained
as being due to the absence of β-hydrogen in alkyl group of these com-
pounds.
All the (E)- and (Z)-sulphide-sulphones underwent the well known
sulphonyl-sulphinate rearrangement12,13 furnishing with subse+quent
cleavages p-CH3C6H4SO+ (139), C6 H += S (121) and C H
= O
5 C
5 C
6
(105). The 121 and 105 peaks are assumed to be formed via thioben-
zil radical cation (Scheme 2). Vinyl migration is the only predominant
pathway observed in sulphonyl-sulphinate rearrangement. McLafferty-
type rearrangement14 was noticed only in (E)-sulphide-sulphones. In
McLafferty-type rearrangement the migration of ortho hydrogen from
p-tolylsulphonyl group to the ethylenic carbon involving a six mem-
bered cyclic transition state is taking place. The ions produced in
this rearrangement by the loss of SO2 gave the ions (III) (Scheme 5).
SCHEME 5

2094
M. Shafi
McLafferty-type rearrangement was not observed in (Z)-sulphide-
sulphones and this may be attributed to the steric interactions present
in these isomers which prevents the formation of the six membered
cyclic transition state.
+.
In the mass spectra of all the (E)- and (Z)-disulphones
peaks
M
were not observed. This may be due to the thermal decomposition of
the samples during sample evaporation. The fragmentation pattern of
(E)-disulphones is shown in Scheme 6. The base peaks in the disul-
phones were observed either at m/z 178 (C6H5C ≡ CC6 H5)+. or m/z 105
+
(C6H
=O). The peak at m/z 333 present in all the disulphones may
5 C
be obtained by the loss of RSO2 from the + . which can further expel
SO2 to give a peak at m/z 269. All the
M
+.
also undergo fragmentation
M
by the loss of p-CH3C6H4SO.2 forming a cation (IV). Smiles-type rear-
rangement was totally absent in all the (E)- and (Z)-disulphones and
this may be attributed to the absence of unshaired electron pair on the
sulphur atoms which are necessary for this rearrangement to occur.
Double sulphonyl-sulphinate rearrangement was observed in all the
(E)- and (Z)-disulphones. This rearrangement followed by subsequent
cleavages formed p-CH3C6H4SO+m/z (139) and C6H5C+ O m/z (105).
Benzoyl cation may be formed via benzil radical cation (Scheme 6).
It is noteworthy that McLafferty-type rearrangement was observed
only in (E)-disulphones involving both thep-tolylsulphonyl group, as
well as alkylsulphonyl groups (having γ -hydrogen) Scheme 7. When
p-tolylsulphonyl group is involved, migration of ortho hydrogen to the
ethylenic carbon via a six membered cyclic transition state occurs and
gave peaks V and VI by the successive loss of one and two molecules of
SO2. The m/z values and intensities of the peaks V and VI are shown
in Table II . When alkylsulphonyl group is involved in McLafferty-
type rearrangement migration of γ -hydrogen to the ethylenic carbon
occurs and results in the formation of peaks at m/z 334 and 270
by the loss of one and two molecules of SO2, respectively. The m/z
334 and 270 peaks were not observed in 4a as it does not contain -
γ hydrogen in alkylsulphonyl group. McLafferty-type rearrangement
was not observed in all the (Z)- disulphones probably due to steric
hindrance.
EXPERIMENTAL
All melting points were determined on
a Mel-Temp appara-
tus and are uncorrected. Mass spectra were recorded on Auto

2095

2096
M. Shafi
SCHEME 7
TABLE II The m/z Values and Intensities of V and VI Peaks Obtained
from (E)-p-CH3C6H4SO2(C6H5)C C (C6H5) SO2R on McLafferty-type
Rearrangement.
V
VI
Comp.
R
m/z (rel.int. %)
m/z (rel.int. %)
4a
4b
4c
4d
4e
4f
4g
4h
4i
CH3
CH3CH2
258 (13)
272 (18)
286 (5)
286 (6)
300 (4)
300 (6)
300 (4)
314 (5)
314 (4)
194 (14)
108 (15)
222 (10)
222 (15)
236 (9)
236 (10)
236 (8)
250 (8)
250 (7)
CH3(CH2)2
(CH3)2CH
CH3(CH2)3
(CH3)2CHCH2
(CH3)3C
CH3(CH2)4
(CH3)2CH(CH)2

Trichlorosilane Reduction of Phosphine Oxides
2097
Spec–M Micro Mass Instrument, Manchester, U.K. (E)-1-Chloro-2-p-
tolylsulphonylstilbene (1) and (Z)-1-bromo-2-p-tolylsulphonylstilbene
(2) were prepared as reported earlier.5
(E)-1-Alkylthio-2-p-tolylsulphonylstilbenes (3a–i)—General
Procedure
A solution of sodium alkanethiolate prepared by adding an appropriate
alkanethiol (6 mmol) to a solution of sodium (6 mg atom) in abs. ethanol
(25 ml) was added to a solution of 1 (6 m mol) dissolved in abs. ethanol
(75 ml). The reaction mixture was heated under reflux. Refluxion time
varied from 5 to 7 h in different cases. In many cases, the solution upon
cooling deposited the sulphide-sulphones, (3) which were recrystallized
from an appropriate solvent.
(E)-1-methylthio-2-p-tolylsulphonylstilbene (3a)
Recrystallized from aqueous ethanol as shining needles, m.p. 172–
173◦C, yield 91% (Found: C, 69.13; H, 5.25; S, 16.61. C22H20O2S2 re-
quires C, 69.44; H, 5.30; S, 16.82%). EIMS: m/z (rel. int.%) 380(37),
333(8), 269(15), 259(12), 226(14), 225(19), 210(42), 179(15), 178(100),
176(8), 155(15), 139(5), 138(6), 126(5), 123(9), 121(22), 105(19), 91(21),
and 78(11).
(E)-1-ethylthio-2-p-tolylsulphonylstilbene (3b)
It was recrystallized from methanol, m.p. 149–50◦C (lit.6 m.p. 149–
50◦C). EIMS: m/z (ret.int.%). 394(26), 333(8), 269(17), 257(16), 240(12),
239(10), 211(36), 210(52), 179(30), 178(100), 176(15), 155(18),152(8),
139(10), 123(15), 121(10), 105(31), 91(20), and 29(5).
(E)-1-n-propylthio-2-p-tolylsulphonylstilbene (3c)
Recrystallized from isopropanol m.p. 141–142◦C (lit.6 m.p. 140—
41◦C). EIMS: m/z (rel.int.%) 408(38), 333(5), 301(5), 269(16), 254(14),
253(79), 243(8), 238(15),211(52), 210(100), 179(15), 178(62), 176(8),
166(42), 165(20), 155(20), 139(21), 123(14), 121(11), 105(10), 91(25), and
43(23).
(E)-1-isopropylthio-2-p-tolylsulphonylstilbene (3d)
Recystallized from ethanol, m.p. 180–181◦C (lit.6 m.p. 180–181◦C).
EIMS: m/z (rel.int.%) 408(36), 333(4), 269(23), 254(16), 253(89), 211(42),
210(100), 179(20), 178(66), 176(10), 166(51), 165(21), 155(18), 139(19),
123(14), 121(11), 91(15), and 43(33).
(E)-1-n-butylthio-2-p-tolylsulphonylstilbene (3e)
It was recrystallized from isopropanol, m.p. 137–138◦C (lit.6 m.p.
136–137◦C). EIMS: m/z (rel.int.%) 422(32), 333(5), 269(30), 268(38),

2098
M. Shafi
267(21), 257(11), 254(4), 253(50), 212(23), 211(26), 210(42), 180(59),
179(13), 178(100), 176(9), 165(25), 155(10), 139(6), 123(7), 121(5),
105(36), 91(49), and 57(22).
(E)-1-isobutylthio-2-p-tolylsulphonylstilbene (3f)
Recrystallized from methanol, m.p. 156-157◦C (lit.6 m.p. 155–156◦C).
EIMS: m/z (rel. int.%) 422(28), 333(6), 269(18), 268(40), 267(26),
257(15), 254(15), 253(15), 212(10), 211(25), 210(35), 180(46), 179(25),
178(100), 165(20), 155(9), 139(6), 123(7), 121(4), 105(28), 91(40), and
57(60).
(E)-1-t-butylthio-2-p-tolylsulphonylstilbene (3g)
It was recrystallized from isopropanol as colorless crystals,
m.p. 161–62◦C, yield 95.1% (Found: C, 71.28; H, 6.12; S, 15.04.
C25H26O2S2requires C, 71.06; H, 6.20; S, 15.14%). EIMS: m/z
(rel.int.%) 422(26), 333(8), 301(4), 269(29), 268(8), 267(30), 212(18),
211(96), 210(30), 180(70), 179(28), 178(100), 165(15), 155(14),
139(11), 123(8), 121(6), 105(18), 91(40),6 9(16), 57(49), 55(14), and
43(19).
(E)-1-n-amylthio-2-p-tolylsulphonylstilbene (3h)
Recrystallized from isopropanol, m.p. 141–142◦C (lit.6 m.p. 141–
142◦C). EIMS: m/z (rel.int.%). 436(24), 333(9), 282(25), 281(26), 269(30),
211(95), 210(100), 194(15), 179(20), 178(83), 165(21), 155(18), 139(20),
123(9), 121(10), 91(21), 71(80), and 43(70).
(E)-1-isoamylthio-2-p-tolylsulphonylstilbene (3i)
It was recrystallized from ethanol, m.p 152–153◦C (lit6. m.p. 151–
152◦C) EIMS: m/z (rel.int.%) 436(25), 333(5), 282(15), 281(29), 269(24),
211(90), 210(100), 194(10), 179(20), 178(85), 176(8), 165(23), 155(10),
139(18), 123(7), 121(8), 91(30), 71(80), and 43(75).
(E)-1-Alkylsulphonyl-2-p-tolylsulphonylstilbenes (4a–i)—
General Procedure
A solution of 3 (15 m mol) in 20 ml of glacial acetic acid was
treated with 30% hydrogen peroxide, and the reaction mixture was
heated under reflux for 1 h. The solid separated, 4, on cooling,
was collected by filtration and recrystallized from an appropriate
solvent.
(E)-1-methylsulphonyl-2-p-tolylsulphonylstilbene (4a)
It was recrystallized from isopropanol, yield 93%, m.p. 211–212◦C
(Found: C, 64.29; H, 4.70; S, 15.68. C22H20O4S2 requires C, 64.05;

Trichlorosilane Reduction of Phosphine Oxides
2099
H, 4.89; S, 15.51%). EIMS: m/z (rel.int.%) 333(3), 269(70), 258(13),
257(39), (IV), 243(16), 210(7), 194 (14), 193(3), 179 (15), 178 (88),
176(12), 155(11), 153(6), 139(9), 123(21), 105(100), 93(10), 91 (64), and
89 (29).
(E)-1-ethylsulphonyl-2-p-tolylsulphonylstilbene (4b)
Recrystallized from acetic acid, m.p. 215–16◦C(lit.6 m.p 214–15◦C).
EIMS : m/z (rel.int.%) 334(5), 333(6), 272(18), 271(19),(IV), 270(82),
269(65), 210(5), 208 (15), 207(11), 179(25), 178(100), 176(12), 155(9),
139(15), 123(5), 105(76), 91(67) and 29(8).
(E)-1-n-propylsulphonyl-2-p-tolylsulphonylstilbene (4c)
It was recrystallized from methanol, m.p. 202–03◦C (lit.6 m.p. 202–
203◦C). EIMS: m/z (rel.int.%) 334(4), 333(6), 286(5), 285(14), (IV),
270(79), 269(62), 222(10), 210(5), 179(10), 178(100), 176(8), 155(8),
139(5), 123(12), 105(45), 91(60), 57(15), and 43(39).
(E)-1-isopropylsulphonyl-2-p-tolylsulphonylstilbene (4d)
Recrystallised from aqueous dioxane, m.p. 233–234◦C (lit.6 m.p.
232–233◦C). EIMS: m/z (rel.int.%) 334(6), 333(4), 286(6), 285(7), (IV),
270(96), 269(55), 244(43), 222(15), 210(6), 179(19), 178(100), 176(9),
155(6), 139(4), 123(19), 105(55), 91(13), 57(22), and 43(93).
(E)-1-n-butylsulphonyl-2-p-tolylsulphonylstilbene (4e)
Recrystallized from ethanol, m.p. 203–204◦C (lit.6 m.p. 203–204◦C).
EIMS: m/z 334(5), 333(6), 300(4), 299(5), (IV), 270(11), 269(63), 243(6),
236(9), 235(11), 210(5), 179(15), 178(72), 176(11), 155(6), 139(8),
123(22), 105(100), 91(60), and 57(53).
(E)-1-isobutylsulphonyl-2-p-tolylsulphonylstilbene (4f)
It was recrystallized from acetic acid, m.p. 224–225◦C (lit.6 m.p.
224–225◦C). EIMS : m/z (rel.int.%) 334(4), 333(4), 300(6), 299(4),(IV),
270(32), 269(60), 236(10), 235(13), 210(4), 179(5), 178(78), 176(10),
155(8), 139(5), 123(26), 105(100), 91(55), 89(19), 57(39), and 55(20).
(E)-1-t-butylsulphonyl-2-p-tolylsulphonylstilbene (4g)
It was recrystallized from ethanol, m.p. 220–221◦C, yield (84%).
(Found : C, 65.98; H, 5.62; S, 14.01. C25H26O4S2 requires C, 66.04; H,
5.76; S, 14.08%). EIMS: m/z (rel.int.%) 334(4), 333(5), 300(4), 299(4),
(IV), 270(30), 269(63), 236(8), 235(15), 210(5), 179(4), 178(72), 176(9),
155(5), 139(4), 123(22), 105(100), 91(60), 89(21), 57(55), and 43(49).

2100
M. Shafi
(E)-1-n-amylsulphonyl-2-p-tolylsulphonylstilbene (4h)
It was recrystallized from acetic acid, m.p. 209–10◦C (lit.6 m.p.
209–210◦C). EIMS:m/z (rel.int.%). 334(4), 333(6), 314(5), 313(5), (IV),
270(26), 269(33) , 250(8), 243(19), 210(6), 179(20), 178(80), 176(15),
155(8), 139(5), 123(17), 105(100), 91(43), 71(70), and 43(60).
(E)-1-isoamylsulphonyl-2-p-tolylsulphonylstilbene (4i)
It was recrystallized from isopropanol, m.p. 210–211◦C (lit.6 m.p
208–209◦C). EIMS: m/z (rel.int.%) 334(6), 333(8), 314(4), 313(4), (IV),
270(18), 269(40), 250(7), 243(20), 210(4), 179(8), 178(83), 176(19),
155(4), 139(9), 123(21), 105(100), 91(50), 71(76), and 43(81).
(Z)-1-alkylthio-2-p-tolylsulphonylstilbenes (5a–i)
General Method
To a solution of sodium ethoxide (5.5 mg atom of sodium dissolved in
10 ml of abs. ethanol) an appropriate alkanethiol (5.5 m mole) was
added. The resulting alkanethiolate solution was mixed with a solution
of 2 (5.5 m mol) in ethanol (50 ml) and refluxed. Reflux time varied
from 3 to 6 h, in different cases. The solution upon cooling deposited
the (Z)-1-alkylthio-2-p-tolylsulphonylstilbenes (5) as crystalline mate-
rial, which was recrystallized from 95% ethanol or any other suitable
solvent.
(Z)-1-methylthio-2-p-tolylsulphonylstilbene (5a)
It was recrystallized from 95% ethanol, yield 94%, m.p. 126–127◦C
(Found:C, 69.42; H, 5.21; S, 16.74. C22H20O4S2 requires C, 69.44; H,
5.30; S, 16.82%). EIMS:m/z (rel.int.%) 380(29), 333(6), 301(10), 269(15),
261(6), 257(15), 225(42), 210(60), 179(15), 178(100), 176(6), 139(5),
138(26), 137(11), 123(7), 121(8), 105(23), 91(15), 78(11), and 51(5).
(Z)-1-ethylthio-2-p-tolylsulphonylstilbene (5b)
Recrystallized from 95% ethanol, m.p. 161–162◦C (lit.6 m.p. 160–
161◦C). EIMS : m/z (rel.int.%) 394(20), 333(5), 269(15), 239(48), 211(31),
210(100), 179(11), 178(56), 176(31), 155(10), 152(15), 139(5), 123(12),
121(22), 105(41), 91(35), and 29(5).
(Z)-1-n-propylthio-2-p-tolylsulphonylstilbene (5c)
Recrystallized from 95% ethanol, m.p. 118–119◦C (lit.6 m.p. 118–
119◦C). EIMS:m/z (rel.int.%) 408(25), 333(6), 269(18), 253(90), 243(4),
211(40), 210(100), 179(15), 178(59), 176(12), 166(50), 155(6), 139(17),
123(10), 121(13), 91(10), and 43(30).

Trichlorosilane Reduction of Phosphine Oxides
2101
(Z)-1-isopropylthio-2-p-tolylsulphonylstilbene (5d)
It was recrystallized from 95% ethanol, m.p. 158–59◦C (lit.6 m.p. 158–
159◦C). EIMS:m/z (rel.int.%) 408(18), 333(3), 269(26), 253(80), 243(9),
211(72), 210(100), 179(20), 178(65), 176(10), 166(45), 155(10), 139(21),
123(5), 121(10), 91(14), and 43(37).
(Z)-1-n-butylthio-2-p-tolylsulphonylstilbene (5e)
It was recrystallized from aqueous ethanol, m.p. 129–130◦C (lit.6
m.p. 128–29◦C) EIMS:m/z (rel.int.%) 422(20), 333(5), 269(10), 267(15),
211(20), 210(76), 180(22), 179(28), 178(100), 176(20), 155(15), 139(6),
123(5), 121(6), 105(36), 91(50), and 57(20).
(Z)-1-isobutylthio-2-p-tolylsulphonylstilbene (5f)
Recrystallized from aqueous isopropanol, m.p. 93–94◦C (lit.6 m.p. 92–
93◦C). EIMS:m/z (rel.int.%) 422(16), 333(4), 269(21), 267(18), 212(5),
211(15), 210(90), 180(26), 179(23), 178(100), 176(13), 167(4), 165(4),
155(19), 139(10), 123(7), 121(5), 91(54), and 57(38).
(Z)-1-t-butylthio-2-p-tolylsulphonylstilbene (5g)
Recrystallized from aqueous ethanol as shining needles, yield 89.7%.,
m.p, 95–96◦C. Found:C, 71.02; H, 6.02; S, 14.98. C25H26O2S2 requires
C, 71.06; H, 6.20; S, 15.14 %). EIMS:m/z (rel. int. %) 422(10), 333(4),
287(15), 269(30), 267(11), 212(10), 211(47), 210(18), 180(34), 179(23),
178(100), 176(10), 167(5), 165(8), 155(11), 139(8), 123(6), 121(10),
105(23), 98(10), 91(26), 73(29), 71(27), 69(49), 67(10), 57(9), and 43(38).
(Z)-1-amylthio-2-p-tolylsulphonylstilbene (5h)
Recrystallized from aqueous ethanol. m.p. 115–116◦C (lit.6 m.p. 115–
116◦C). EIMS:m/z (rel. int.%) 436(14), 333(6), 301(29), 281(32), 269(15),
211(90), 210(100), 194(18), 179(23), 178(50), 176(15), 165(19), 155(6),
139(23), 123(7), 121(5), 105(18), 91(20), 71(81), 57(5), 43(80), and 41(9).
(Z)-1-isoamylthio-2-p-tolylsulphonylstilbene (5i)
It was recrystallized from aqueous isopropanol, m.p. 130–131◦C (lit.6
m.p. 130–131◦C). EIMS:m/z (rel.int.%) 436(16), 333(7), 301(4), 281(40),
269(16), 211(95), 210(100), 194(24), 179(19), 178(58), 176(10), 165(22),
155(5), 139(25), 123(5), 121(7), 105(27), 91(15), 71(97), 57(6), 43(98),
and 41(11).
(Z)-1-alkylsulphonyl-2-p-tolylsulphonylstilbenes
(6a–i)—General Procedure
A solution of 5 (2 m mol) in glacial acetic acid (50 ml) was mixed with
an excess of 30% hydrogen peroxide (10 ml). The reaction mixture was

2102
M. Shafi
heated to boiling for 1 min, the solution was allowed to stay for 1 h
at room temperature, and then it was poured onto crushed ice. The
disulphones, 6, separated were filtered and recrystallized from an ap-
propriate solvent.
(Z)-1-methylsulphonyl-2-p-tolylsulphonylstilbene (6a)
Recrystallized from acetic acid m.p. 188–189◦C, yield (89.6%) (Found:
C, 63.81; H,5.02; S, 15.78; C20H22O4S2 requires C, 64.05; H, 4.89; S,
15.78%). EIMS : m/z (rel.int.%) 333(31), 269(69), 257(21), (IV), 243(23),
210(9), 179(19), 178(100), 176(7), 155(4), 139(6), 123(15), 105(34), and
91(37).
(Z)-1-ethylsulphonyl-2-p-tolylsulphonylstilbene (6b)
It was recrystallized from isopropanol, m.p. 176–177◦C (lit.6 m.p.
176–177◦C). EIMS : m/z (rel. int. %) 333(35), 271(15), (IV), 269(58),
210(6), 179(11), 178(100), 176(6), 155(8), 139(7), 123(10), 91(41), and
29(5).
(Z)-1-n-propylsulphonyl-2-p-tolylsulphonylstilbene (6c)
Recrystallized from methanol, m.p 162–163◦C (lit.6 m.p. 161–162◦C).
EIMS: m/z (rel. int. %) 333(8), 285(10),(IV), 269(50), 210(5), 179(20),
178(100), 176(15), 155(10), 139(8), 123(23), 105(47), 91(40), and 43(25).
(Z)-1-isopropylsulphonyl-2-p-tolylsulphonylstilbene (6d)
It was recrystallized from methanol, m.p. 198–199◦C (lit.6 m.p. 198–
199◦C). EIMS: m/z (rel. int. %) 333(6), 285(11), (IV), 269(65), 210(6),
179(16), 178(100), 176(6), 155(12), 123(21), 105(45), 91(60), and 43(39).
(Z)-1-n-butylsulphonyl-2-p-tolylsulphonylstilbene (6e)
Recrystallized from isopropanol, m.p. 158–159◦C (lit.6 m.p. 157–
158◦C). EIMS: m/z (rel.int.%) 333(4), 299(4), (IV), 269(75), 243(6),
210(8), 179(10), 178(88), 176(16), 155(7), , 139(5), 123(21), 105(100),
91(61), and 57(18).
(Z)-1-isobutylsulphonyl-2-p-tolylsulphonylstilbene (6f)
It was recrystallized from isopropanol, m.p. 164–165◦C (lit.6 m.p.
164–165◦C) EIMS: m/z (rel.int.%) 333(4), 299(4), (IV), 269(70) 243(7),
210(5), 179(19), 178(80), 176(14), 155(5), 139(9), 123(25), 105(100),
91(69), 57(10), and 41(20).
(Z)-1-t-butylsulphonyl-2-p-tolylsulphonylstilbene (6g)
Yield (80.5%) Recrystallized from isopropanol as colorless needles,
m.p. 168–169◦C (Found: C, 65.80; H, 5.52; S, 13.89, C25H26O4S2 requires

Trichlorosilane Reduction of Phosphine Oxides
2103
C, 66.06; H, 5.76; S, 14.08%) EIMS: m/z (rel. int %) 333(4), 299(5),
(IV), 269(75), 235(10) 210(6), 179 (15), 178(90), 176(10), 155(8), 139(6),
123(21), 105(100), 91(64), 89(28), 57(73), and 55 (30).
(Z)-1–n-amylsulphonyl-2-p-tolylsulphonylstilbene (6h)
It was recrystallized from isopropanol, m.p.136–137◦C (lit,6 m.p.136–
137◦C). EIMS: m/z (rel.int%) 333(5), 313 (4), (IV), 269(51), 243(20),
210(5), 179(18), 178(100), 176(12), 155(12), 139(15), 123(18), 105(48),
91(21), 71(52), and 43(20).
(Z)-1-isoamylsulphonyl-2-p-tolylsulphonylstilbene (6i)
Recrystallized from 95%, ethanol, m.p. 125–126◦C (lit.6 m.p. 123–
124◦C) EIMS: 333(6), 313 (4), (IV) 269 (69), 243 (22), 210(4), 179(20),
178 (100), 176 (10), 155(8), 139 (11), 105(30), 91(31), 71(65), and 43 (71).
REFERENCES
[1] M. S. Raasch, U.S. Patent, 2,979,435 (1961); Chem. Abstr., 54 (1960).
[2] (a) J. D. Johnston, German Patent, 1,065,659 (1959); Chem. Abstr.,55, 15820 a
(1961); (b) J. D. Johnston U.S. Patent, 3052397 (1962), Chem. Abstr., 57, 14236
e (1962).
[3] H. J. Gerjovich, U.S. Patent, 2983 762 (1961); Chem. Abstr., 55, 19793 h (1963).
[4] L. Benati, M. Tiecco, and A. Tundo, Bull. Sci. Fac. Chim. Ind. Bologna, 21, 177
(1963).
[5] M. S. R. Naidu and S. G. Peeran,Tetrahedron, 31, 465 (1975).
[6] M. S. R. Naidu, S. G. Peeran, and D. B. Reddy, Indian J. Chem., 16B, 1086 (1978).
[7] S. Ghouse Peeran, T. Hidayathulla Khan, and R. Venkateswarlu, Indian J. Chem.,
21 B, 579 (1982).
[8] S. Ghouse Peeran, Y. Vatsala, C. Khasim Sahib, and G. Hanumantha Reddy,
Phosphorous, Sulphur, and Silicon, 62, 181 (1991).
[9] F. Montanari, Gazz. Chim. Ital., 86, 228, 406, 735, 747 (1956).
[10] G. Modena and P. E . Todesco, Gazz. Chim. Ital., 89, 866 (1959).
[11] C. J. Hill, B. S. Thyagarajan, D. K. Bates, and R. J. Spangler, Org. Mass Spectrom.,
12, 370 (1979).
[12] H. Budzikiewiz, C. Djerassi, and D. H. Williams, Mass Spectrometry of Organic
Compounds, (Holden-Days, San Franscisco 1967).
[13] S. G. Peeran, Y. Sujatha, and G. Hanumantha Reddy, Sulphur Letters, 11, 47 (1990).
[14] L. K. Liu and C. T. Hong, Org . Mass Spectrom., 13, 675 (1978).