Hydrothiolysis of carbofunctional α,β-unsaturated sulfides as an approach to the synthesis of 1,7-dithiocarbonyl compounds

Article abstract of DOI:10.1134/S1070428006080185

Bis(1-N,N-dimethylimmonio-3-phenylprop-2-en-3-yl) sulfide diperchlorate and (1-N,N-dimethyl-immonio-3-phenylprop-2-en-3-yl) (5,5-dimethyl-1- morpholiniocyclohex-2-en-3-yl) sulfide diperchlorate react with hydrogen sulfide giving rise to the corresponding

Full text of DOI:10.1134/S1070428006080185

ISSN 1070-4280, Russian Journal of Organic Chemistry, 2006, Vol. 42, No. 8, pp. 1208-1212. Ó Pleiades Publishing, Inc. 2006.
Original Russian Text Ó L.V. Timokhina, O.V. Sokol’nikova, L.V. Kanitskaya, M.P. Yashchenko, D.-S.D. Toryashinova, M.G. Voronkov, 2006,
published in Zhurnal Organicheskoi Khimii, 2006, Vol. 42, No. 8, pp. 1227-1231.
Hydrothiolysis of Carbofunctional a,b-Unsaturated Sulfides
as an Approach to the Synthesis of 1,7-Dithiocarbonyl Compounds
L.V. Timokhina, O.V. Sokol’nikova, L.V. Kanitskaya, M.P. Yashchenko,
D.-S.D. Toryashinova, and M.G. Voronkov
Faworsky Irkutsk Institute of Chemistry, Siberian Division, Russian Academy of Sciences, Irkutsk, 664033 Russia
e-mail: tim@irioch.irk.ru
Received May 23, 2005
Abstract—Bis(1-N,N-dimethylimmonio-3-phenylprop-2-en-3-yl) sulfide diperchlorate and (1-N,N-dimethyl-
immonio-3-phenylprop-2-en-3-yl) (5,5-dimethyl-1-morpholiniocyclohex-2-en-3-yl) sulfide diperchlorate react with
hydrogen sulfide giving rise to the corresponding 1,7-thioxoimmonio sulfides. Treating with the hydrogen sulfide
(1-N,N-dimethylimmonio-3-phenylprop-2-en-3-yl) (1-oxo-2-phenyl-inden-3-yl) sulfide perchlorate led to preparation
of (1-oxo-2-phenylinden-3-yl) (1-thioxo-3-phenylprop-2-en-3-yl) sulfide. The hydrothiolysis of (5,5-dimethyl-
1-morpholiniocyclohex-2-en-3-yl) (1-N,N-dimethylimmonio-2-phenylinden-3-yl) sulfide diperchlorate and
(5,5-dimethyl-1-morpholiniocyclohex-2-en-3-yl) (1-oxo-2-phenylinden-3-yl) sulfidea perchlorate resulted in products
of the sulfide bond cleavage in the initial immonium salts.
DOI: 10.1134/S1070428006080185
The most efficient among the preparation methods we
tested to synthesize the first unsaturated 1,7-dithione,
bis(5,5-di-methyl-3-thioxocyclohex-1-enyl) sulfide (I),
proved to be the hydrothiolysis at low temperature of the
corresponding bisimmonium salt II [1, 2].
containing propenyl, cyclohexenyl, and indenyl substitu-
ents.
The hydrothiolysis of immoniothioxo-substituted
(5,5-dimethyl-1-morpholiniocyclohex-2-en-3-yl) (5,5-dim-
ethyl-1-thioxocyclohex-2-en-3-yl) sulfide perchlorate (III)
occurring with a rupture of the C–S bond in the initial
compound and resulting in the formation of enaminothio-
ketone IV was described in [2].
0H
0H
0H
0H
0H
0H
0H
0H
2
1
6
1
2
&O2
&O2
0H
,,
6
6
1
2
0H
0H
0H
&O2
,,,
+6
0H&1ꢀꢁꢁ ꢂꢃ &
0H
0H
6
6
6
+6
0H&1ꢀꢁꢁ ꢄꢅ &
,
6
1
2
In the present study aiming at preparation of new
representatives of 1,7-dithioxo-substituted systems and also
of their monooxygen analogs we investigated the
hydrothiolysis of bisimmonio- and immoniooxo-substituted
symmetric and unsymmetrical a,b-unsaturated sulfides
,9
We failed to obtain another such sulfide, namely
(1-N,N-dimethylimmonio-3-phenylprop-2-en-3-yl) (5,5-di-
methyl-1-thioxocyclohex-2-en-3-yl) sulfide perchlorate
1208

HYDROTHIOLYSIS OF CARBOFUNCTIONALa,b-UNSATURATED SULFIDES
1209
0H
10H
&O2
3K
0H
3K
ꢀ
6
&O
10H
&O2
6
6+
0H
3K
10H
&O2
9,
9,,,
9,,
0H
3K
6
6
10H
&O2
9
By reaction of (1-N,N-dimethylimmonio-3-phenylprop-
2-en-3-yl) (5,5-dimethyl-1-morpholinio-cyclohex-2-en-3-
yl) sulfid diperchlorate (XII) [3] with hydrogen sulfide in
DMF we obtained 5,5-dimethyl-4-mercapto-7-morpho-
linio-2-phenyl-2,3,5,6-tetrahydro-7H-thiochromen perchlo-
rate (XIII). Its formation may be attributed to the
heterocyclization of the primarily arising (1-thioxo-3-
phenylprop-2-en-3-yl) (5,5-dimethyl-1-morpholiniocyclo-
hex-2-en-3-yl) sulfide perchlorate (XIV). We formerly
observed a similar formation of thiochromen derivatives
[6].
(V), by reaction of 5,5-dimethyl-3-mercaptocyclohex-2-
ene-1-thione (VI) with N-(3-phenyl-3-chloroprop-2-en-
1-ylidene)-N,N-dimethylimmonium perchlorate (VII).
Instead of the expected compound V we isolated bis(1-
N,N-dimethylimmonio-3-phenylprop-2-en-3-yl) sulfide
diperchlorate (VIII).
The purposeful synthesis of bisimmonio-substituted
sulfides was performed applying the reaction of enamino-
thioketones with immonium haloderivatives perchlorates
[3], and immoniooxo-substituted derivatives were prepara-
ed by treating the enaminothioketones with 3-bromo-2-
phenylinden-1-one [4].
The reaction of symmetric diperchlorate VIII [3] with
hydrogen sulfide in DMF at –60°C led to the formation
of (1-thioxo-3-phenylprop-2-en-3-yl) (1-N,N-dimethyl-
immonio-3-phenylprop-2-en-3-yl) sulfide perchlorate (IX),
a product of hydrothiolysis of one immonium group in salt
VIII, and also to the formation of (1-thioxo-3-phenylprop-
2-en-3-yl) (1-N,N-dimethyamino-3-phenylprop-1-en-3-yl)
sulfide (X) and of the known 3-N,N-dimethylamino-1-
phenylprop-2-en-1-thione (XI) [5].
0H
0H
3K
+
2
1
6
10H
&O2
+
6
&O2
;,,
0H
0H
6
3K
+ 6
3K
+
+6
1+0H ꢀ
+&O2
9,,,
6
2
1
6
+
&O2
3K
10H
&O2
;,9
0H
,;
6+
6
6
0H
3K
3K
10H
ꢀ
+
ꢀ
6
2
1
3K
6
3K
10H
&O2
;
;,
;,,,
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 42 No. 8 2006

TIMOKHINA et al.
0H
1210
0H
0H
0H
10H
3K
+6
ꢀ
1
2
6
1
2
6
0H 1
&O2
6
&O2
3K
;9
,9
;9,
2
3K
2
6
2
6+
;9,,
3K
3K
;9,,,
The hydrothiolysis of (5,5-dimethyl-1-morpholinio-
cyclohex-2-en-3-yl) (1-N,N-dimethylimmonio-2-phenyl-
indene-3-yl) sulfide diperchlorate (XV) in DMF or ac-
etonitrile in the presence of triethylamine at low tem-
perature (–40...–60°C) caused the cleavage of the C–S
bond in initial salt XV to produce compounds containing
cyclohexene or indene fragments. We identified among
the reaction products 5,5-dimethyl-3-morpholinocyclohex-
2-ene-1-thione (IV) [7], 3-N,N-dimethylamino-2-phenyl-
indene-1-thione (XVI) [8], and also 3-oxo-2-phenyl-1-
indenethiol (XVII), and bis(1-oxo-2-phenylinden-3-yl)
sulfide (XVIII) [9].
thioxo-3-phenylprop-2-en-3-yl) sulfide (XXI) as a mix-
ture of two geometric isomers.
3K
2
6
10H
&O2
3K
;;
+6
3K
The treating with the hydrogen sulfide of (5,5-dim-
ethyl-1-morpholiniocyclohex-2-en-3-yl) (1-oxo-2-phenyl-
inden-3-yl) sulfide perchlorate (XIX) [4] (acetonitrile, tri-
ethylamine, –40°C) also resulted in the rupture of the
sulfide bond in initial salt XIX and in formation of
enaminothioketone IV [7], oxothiol XVII, and dioxosulfide
XVIII [9].
2
6
6
3K
;;,
Thus the study of the hydrothiolysis of carbofunctional
a,b-unsaturated sulfides demonstrated that the course of
the reaction depended on the character of the substitu-
ents attached to the fragment C=C–S–C=C. The target
1,7-dithiocarbonyl compound we succeeded to synthesize
only from bis-(5,5-dimethyl-1-morpholiniocyclohex-2-en-
3-yl) sulfide diperchlorate (II) [1]. By the hydrothiolysis
of immoniooxo-substituted salt XX a monooxygen analog
of the dithioxosulfide was obtained. In all other cases
formed either 1,7-thioxoimmonio-substituted derivatives
or the products of the initial sulfide fragmentation due to
the cleavage of the C–S bond.
0H
0H
1
2
6
2
&O2
3K
+6
;,;
,9ꢀꢆꢀ;9,,ꢀꢆꢀ;9,,,
(1-N,N-Dimethylimmonio-3-phenylprop-2-en-3-yl) (1-
oxo-2-phenylinden-3-yl) sulfide perchlorate (XX) [4] re-
acted with the hydrogen sulfide (DMF, –60°C) at the
carboiminium group with the retention of the divinyl sul-
fide fragment giving rise to (1-oxo-2-phenylinden-3-yl (1-
EXPERIMENTAL
IR spectra were recorded on a spectrophotometer IFS-
1
25 from samples in KBr pellets. H NMR spectra were
registered on spectrometers Jeol FX-90Q and Bruker
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 42 No. 8 2006

HYDROTHIOLYSIS OF CARBOFUNCTIONALa,b-UNSATURATED SULFIDES
1211
DPX-400, extenal reference HMDS. The reaction
progress was monitored and the purity of products ob-
tained was checked by TLC on Silufol UV-254 plates
using as eluent a mixture chloroform–ethyl acetate, 3:1.
Hydrothiolysis of (1-N,N-dimethylimmonio-3-
phenylprop-2-en-3-yl) (5,5-dimethyl-1-morpholinio-
cyclohex-2-en-3-yl) sulfide diperchlorate (XII). Into
a solution of 0.24 g (0.4 mmol) of salt XII in 5 ml of DMF
at 20°C was passed for 30 min a flow of dry hydrogen
sulfide. The reaction mixture was poured into 30 g of ice-
water mixture. The separated precipitate was filtered off,
washed with water, and dried in a vacuum desiccator
over CaCl2. We obtained 0.15 g (80%) of 5,5-dimethyl-
4-mercapto-7-morpholinio-2-phenyl-2,3,5,6-tetrahydro-
7H-thiochromen perchlorate (XIII) as a powder of mus-
Reaction of 5,5-dimethyl-3-mercaptocyclohex-2-
ene-1-thione (VI) with N-(3-phenyl-3-chloroprop-2-
en-1-ylidene)-N,N-dimethylimmonium perchlorate
(VII). To a solution of 0.52 g (3 mmol) of enthiolthione
VI in 20 ml of anhydrous methanol at 10°C under argon
atmosphere was added while stirring 0.88 g (3 mmol) of
perchlorate VII. The reaction mixture was stirred for 4 h
and was left overnight at 5°C. The precipitate formed
was filtered off and washed with methanol. We obtained
0.63 g (38%) of bis(1-N,N-dimethylimmonio-3-phenyl-
prop-2-en-3-yl) sulfide diperchlorate (VIII) as a yellow
powder, t.decomp. 178–195°C. The decomposition tem-
–1
tard color, mp 123–125°C. IR spectrum, n, cm : 623 and
1096 (ClO4), 1556, 1576 (C=C), 1651 (C=N+), 2484 (SH).
1H NMR spectrum (DMSO-d6), d, ppm: 0.82 and 0.87 s
(6H, CH3), 2.44 m (2H, 6-CH2), 2.64 m (2H, 3-CH2),
3.55 s (1H, SH), 3.66 m (1H, 2-CH), 3.67 and 3.83 m
(8H, morpholine), 6.30 s (1H, HC=), 7.35–7.57 m (5H,
C6H5). 13C NMR spectrum (DMSO-d6), d, ppm: 27.4,
27.6 (CH3), 34.5 (C5), 43.0 [=N+(CH2)2], 50.3 (C6), 50.9
(C3), 63.4 [O(CH2)2], 66.1 (C2), 110.0 (C=N+), 122.1
(=C–H), 127–140 (CPh, C4, C9, C10). Found, %: C 54.20;
H 5.45; Cl 6.84; N 2.17; S 13.82. C21H26ClNO5S2. Cal-
culated, %: C 53.45; H 5.51; Cl 7.53; N 2.97; S 13.57.
1
perature, IR and H NMR spectra of compound VIII
were identical to those published in [3]. Found, %: C 48.16;
H 4.73; N 5.18; S 5.81. C22H26Cl2N2O8S. Calculated, %:
C 48.09; H 4.74; N 5.10; S 5.83.
Hydrothiolysis of bis(1-N,N-dimethylimmonio-3-
phenylprop-2-en-3-yl) sulfide diperchlorate (VIII).
Into a solution of 0.38 g (0.7 mmol) of salt VIII in 4 ml of
DMF at –60°C was passed for 4 h a flow of dry hydro-
gen sulfide. The reaction mixture was poured into 50 g of
ice-water mixture. The separated precipitate was filtered
off, repeatedly washed with water, and dried in a vacuum
desiccator over P2O5. We obtained 18 g of a mixture
containing (1-thioxo-3-phenylprop-2-en-3-yl) (1-N,N-
dimethylimmonio-3-phenylprop-2-en-3-yl) sulfide perchlo-
rate (IX) and (1-thioxo-3-phenylprop-2-en-3-yl)(1-N,N-
dimethyl-amino-3-phenylprop-1-en-3-yl)sulfide (X) as
(5,5-Dimethyl-1-morpholiniocyclohex-2-en-3-yl)
(1-N,N-dimethylimmonio-2-phenylinden-3-yl) sul-
fide diperchlorate (XV). To a solution of 0.33 g (1 mmol)
of 5,5-dimethyl-3-chlorocyclohex-2-ene-1-morpholinium
perchlorate (XXII) [10] in 15 ml of anhydrous methanol
was added 0.15 g (1.2 mmol) of NaClO4, and while stir-
ring and heating to 40–45°C was added by portions
0.27 g (1 mmol) of 3-N,N-dimethylamino-2-phenylindene-
1-thione (XVI) [8]. The reaction mixture was stirred for
3 h, then cooled, the separated dark-red precipitate was
filtered off, washed with anhydrous methanol, and dried
in a vacuum desiccator over P2O5. Yield 0.42 g (64%),
–1
an orange powder. IR spectrum, n, cm : 623 and 1092
(ClO4), 1545, 1601 (C=C–S, C=C), 1644 (C=N+). 1H NMR
spectrum (CD3CN), d, ppm: 3.50 and 3.70 s [6H,
=N+(CH3)2], 6.60 d (1H, =CHCH=N+), 7.01 d (1H,
=CHCH=S), 8.50 d (1H, CH=S), 8.90 d (1H, HC=N+)
(for compound IX); 2.64 s (1H, CH), 3.04 and 3.24 s
[6H, N(CH3)2], 6.88 d (1H, CH=CHN), 6.99 d (1H,
=CHCH=S), 8.32 d (1H, CH=S), 8.80 d (1H, =CHN)
(for compound X); 7.37 m (10H, Harom). The coupling
constant 3Jn–n for groups =CHCH= in compounds IX and
X has the same value equal to 6.8 Hz. The filtrate from
compounds IX and X was treated with chloroform, the
chloroform solution was washed with water and dried
over Na2SO4. On evaporation of the solvent the resi-
due (0.07 g) was investigated by TLC (eluent ethyl ac-
–1
mp 190–193°C. IR spectrum, n, cm : 623 and 1091
1
(ClO4), 1586 (C=C–S), 1566, 1647 (C=N+). H NMR
spectrum (DMF-d6), d, ppm: 1.06 s (6H, CH3), 2.72 m
(2H, 4-CH2), 2.88 m (2H, 6-CH2), 3.50 s [6H,
=N+(CH3)2], 3.70 and 3.94 m (CH2N+CH2 and
CH2OCH2), 6.94 s (1H, HC=), 7.55 m (9H, Harom).
Found, %: C 52.07; H 5.61; Cl 11.51; N 4.16; S 4.77.
C29H34Cl2N2O9S. Calculated, %: C 52.97; H 5.17;
Cl 10.81; N 4.26; S 4.87.
Hydrothiolysis of compound XV. a. Into a solution
of 1.0 g (1.5 mmol) of salt XV in 18 ml of DMF was
passed at –60°C for 7 h a flow of dry hydrogen sulfide.
The reaction mixture was poured into 100 g of ice-water
mixture. The separated bright-brown precipitate was fil-
tered off, repeatedly washed with ice water, and dried in
a vacuum desiccator over P2O5 at 5°C. We obtained
–1
etate) and IR spectroscopy [n (C=S) 1117 cm ]; by com-
parison with an authentic substance [5] the presence
of 3-N,N-dimethyl-amino-1-phenylprop-2-ene-1-thione
(XI) was detected.
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 42 No. 8 2006

TIMOKHINA et al.
1212
a mixture of compounds (0.4 g) containing according to
TLC and IR spectrum 3-N,N-dimethylamino-2-phenylind-
ene-1-thione (XVI) [8], 3-oxo-2-phenylindene-1-thiol
(XVII) [9], bis(1-oxo-2-phenylinden-3-yl) sulfide (XVIII)
[9], and also unidentified substances. IR spectrum, n,
cm : 1253 (C=S) (compound XVI), 1689 (C=O), 2537
(SH) (compound XVII), 1597 (C=C–S), 1707 (C=O)
(compound XVIII).
In the reaction mixture separated from the precipitate
of compounds XVII and XVIII we detected by means
–1
of TLC and IR spectroscopy [n, cm : 1116 (C=S), 1522
(C=C)] the presence of enaminothioketone IV [7].
Hydrothiolysis of (1-N,N-dimethylimmonio-3-
phenylprop-2-en-3-yl) (1-oxo-2-phenylinden-3-yl)
sulfide perchlorate (XX). Into a solution of 0.25 g
(0.5 mmol) of salt XX in 18 ml of DMF a flow of dry
hydrogen sulfide was passed at –60°C for 6 h. The re-
action mixture was poured into 50 g of ice-water mix-
ture. The separated precipitate was filtered off, washed
with ice water, dried in a vacuum desiccator over P2O5,
and then subjected to chromatography on silica gel (40/
100 mesh, solvent and eluent chloroform–ethyl acetate,
3:1). We obtained 0.1 g (55%) of (1-oxo-2-phenylinden-
3-yl) (1-thioxo-3-phenylprop-2-en-3-yl) sulfide (XXI) as
–1
The filtrate was treated with chloroform, the chloro-
form solution was washed with water and dried with
Na2SO4. On evaporating the solvent the residue was dis-
solved in ethyl acetate and passed through a column
packed with silica gel (70/230 mesh), eluent chloroform–
ethyl acetate, 3:1. We obtained 0.26 g (77%) of orange
crystals of 5,5-dimethyl-3-morpholinocyclohex-2-ene-1-
thione (IV), mp 159–162°C (publ.: mp 161–162°C [7]).
–1
orange crystals, mp 77–80°C. IR spectrum, n, cm : 1595
–1
IR spectrum, n, cm : 1116 (C=S), 1522 (C=C).
(C=C–S), 1662 (C=C), 1707 (C=O). 1H NMR spectrum
(CDCl3), d, ppm: 6.20 and 6.37 d (1H, HC=), 6.8–7.6 m
(14H, Harom), 9.26 and 10.40 d (1H, CH=S). Found, %:
C 74.12; H 4.20; S 16.78. C24H16OS2. Calculated, %:
C 75.00; H 4.17; S 16.67.
b. Into a solution of 0.3 g (0.45 mmol) of diperchlorate
XV in 10 ml of anhydrous acetonitrile was passed at
–40°C for 20 min a flow of dry hydrogen sulfide, then
0.01 ml of triethylamine was added, and a flow of dry
hydrogen sulfide was passed at the same temperature
for 2 h. The reaction mixture was poured into 50 g of
a mixture ice-chloroform. The chloroform layer was sepa-
rated, washed with water, and dried with Na2SO4. The
solvent was partly evaporated in a vacuum, and the resi-
due was subjected to column chromatography on silica
gel (70/230 mesh), eluent chloroform–ethyl acetate, 2:1.
We obtained 0.08 g (40%) of red crystals of
The study was carried out under a financial support
from a grant of the President of the Russian Federation
(NSh-1129.2003.03) and of the Russian Foundation for
Basic Research (grant no. 05-03-32036).
REFERENCES
1. Timokhina, L.V., Panova, G.M., Toryashinova, D.-S.D.,Alba-
nov,A.I., , Sokol’nikova, O.V., andVoronkov, M.G., Zh. Org.
Khim., 1999, vol. 35, p. 1436.
2. Timokhina, L.V., Panova, G.M., Kanitskaya, L.V., Sokol’niko-
va, O.V., Toryashinova, D.-S.D., and Voronkov, M.G., Zh.
Org. Khim., 2001, vol. 37, p. 1725.
–1
bis(oxoindenyl) sulfide XVIII. IR spectrum, n, cm : 1600
(C=C–S), 1709 (C=O) and 0.04 g (40%) of orang crys-
–1
tals of thioketone IV. IR spectrum, n, cm : 1117 (C=S),
1523 (C=C) (cf with method a).
Hydrothiolysis of (5,5-dimethyl-1-morpholinio-
cyclohex-2-en-3-yl) (1-oxo-2-phenylinden-3-yl) sul-
fide perchlorate (XIX). Into a solution of 0.25 g
(0.5 mmol) of perchlorate XIX in 20 ml of anhydrous
acetonitrile was passed at –40°C for 15 min a flow of dry
hydrogen sulfide, then 0.01 ml of triethylamine was added,
and a flow of dry hydrogen sulfide was passed at the
same temperature for 10 h. The reaction mixture was
flushed with argon at –40°C till complete removal of the
hydrogen sulfidea. The solution over the precipitate was
removed with a pipette, the precipitate was washed with
cooled acetonitrile and dried in a vacuum at low tem-
perature. We obtained 0.05 g of a red powder containing
a mixture of oxoindenethiol XVII and dioxosulfide
3. Timokhina, L.V., Usov, V.A., Voronkov, M.G., Kozyreva, O.B.,
Panova, G.M., andYashchenko, M.P., Zh. Org. Khim., 1995,
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–1
XVIII. IR spectrum, n, cm : 1684 (C=O), 2536 (SH)
(oxothiol XVII); 1595 (C=C–S), 1705 (C=O) (dioxosulfide
XVIII) (cf. [9]).
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 42 No. 8 2006