Specific features of the reactions of 2,3-dichloro-1-propene with dibenzylchalcogenides in the system hydrazine hydrate-alkali

Article abstract of DOI:10.1134/S1070363214030050

Dibenzyldisulfide and -diselenide react with 2,3-dichloro-1-propene in the system hydrazine hydrate-KOH by the domino mechanism: nucleophilic substitution of the allyl chlorine, dehydrochlorination with participation of the chlorine atom at the sp ^2<

Full text of DOI:10.1134/S1070363214030050

ISSN 1070-3632, Russian Journal of General Chemistry, 2014, Vol. 84, No. 3, pp. 439–443. © Pleiades Publishing, Ltd., 2014.
Original Russian Text © E.P. Levanova, V.A. Grabel’nykh, V.S. Vakhrina, N.V. Russavskaya, A.I. Albanov, I.B. Rozentsveig, N.A. Korchevin, 2014,
published in Zhurnal Obshchei Khimii, 2014, Vol. 84, No. 3, pp. 380–384.
Specific Features of the Reactions of 2,3-Dichloro-1-propene
with Dibenzylchalcogenides
in the System Hydrazine Hydrate–Alkali
E. P. Levanova, V. A. Grabel’nykh, V. S. Vakhrina, N. V. Russavskaya,
A. I. Albanov, I. B. Rozentsveig, and N. A. Korchevin
A.E. Favorskii Irkutsk Institute of Chemistry, Siberian Branch, Russian Academy of Sciences,
ul. Favorskogo 1, Irkutsk, 664033 Russia
е-mail: venk@irioch.irk.ru
Reseived April 23, 2013
Abstract―Dibenzyldisulfide and -diselenide react with 2,3-dichloro-1-propene in the system hydrazine
hydrate–KOH by the domino mechanism: nucleophilic substitution of the allyl chlorine, dehydrochlorination
with participation of the chlorine atom at the sp2-carbon atom, allene–acetylene rearrangement, nucleophilic
addition of the chalcogenide reagent to the triple bond. The effect of the nature of the chalcogen atom and the
benzyl substituent on the studied domino reaction is discussed.
DOI: 10.1134/S1070363214030050
2,3-Dichloro-1-propene (I) is a reactive species
containing two chlorine atoms at the carbon atoms
with different hybridization. Compound I can react
with chalcogen-containing nucleophiles in several
ways depending on the nature of the chalcogen in the
reactant, reaction conditions and the ratio of the
reagents. In the systems hydrazine hydrate–base, in
which chalcogenide anions are readily generated from
elemental chalcogens or organic dichalcogenides [1],
the following possibilities were found: substitution by
chalcogenide group only the chlorine atom at the sp3-
carbon atom [2, 3]; elimination of both chlorine atoms
with the formation of allene [2, 4]; the sequence of
reactions including substitution of the allyl chlorine
followed by dehydrochlorination with the formation of
allenyl compounds, allene-acetylene rearrangement,
and nucleophilic addition of the chalcogenide reagent
to the triple bond (the domino reaction) [5, 6]. These
domino reactions with the use of diphenyldisulfide or
-diselenide are readily controlled and allow to prepare
the promising for organic synthesis unsaturated
organochalcogen compounds (chloropropenyl, allenyl,
acetylene chalcogenides and vinyl bischalcogenides)
with rather high selectivity [5, 6].
in organylchalcogenide ions on the processes of
substitution and dehydrohalogenation with participa-
tion of chlorine atoms attached to the sp3- and sp2-
hybridized carbon atoms, we have studied the reactions
of 2,3-dichloro-1-propene (I) with dibenzyldisulfide
IIа and -diselenide IIb in the system hydrazine
hydrate–KOH. The presence of benzylchalcogenide
fragments and multiple bonds in the structure of the
expected products of these transformations allows to
consider them as potential biologically active com-
pounds or their precursors as well as promising syn-
thons. For example, the use of the benzyl group in
organic synthesis as a protecting group of thiols is well
known [7], in particular, in the synthesis of poly-
peptides [8].
Dibenzyldichalcogenides Bn2Y2 (IIa, Y = S; IIb,
Y = Se), like other dichalcogenides [1] in the system
hydrazine hydrate–KOH are reduced to chalcogenolate
ions [Eq. (1)].
2Bn2Y2 + 4KOH + N2H4·H2O → 4BnYK + N2 + 5H2O, (1)
IIа, IIb
Y = S (а), Se (b).
Taking into account the earlier obtained results
[1, 5, 6] we have used the molar ratio Bn2Y2 : KOH =
1 : 5 for complete reduction of dichalcogenides.
With the goal of further investigation of the effect
of the nature of the chalcogen atom and the substituent
439

440
LEVANOVA et al.
Ratio of the products of the domino reaction of diphenyl-
[5, 6] and dibenzyldichalcogenides (IIа, IIb) with 2,3-
dichloro-1-propene (I) (30–35°С, 2 h, R2Y2 : KOH = 1 : 5,
the yields are given in % in brackets)
As can be seen from the table, the degree of
conversion in the sequence of reactions presented in
scheme (2) decreases for the same R on going from the
thiolate to selenolate ions, and is substantially de-
creased from R = Ph to R = Bn. The increase of the alkali
concentration in the reaction mixture (R2Se2 : KOH =
1 : 10) for Ph2Se2 results in complete conversion of the
first product of the domino reaction, 2-chloro-3-
phenylselanyl-1-propene [6]; for Bn2Se2 (IIb), the
degree of conversion of product IIIb is also increased.
Only in these conditions (Bn2Se2 : KOH = 1 : 10, 30–
35°С, 2 h) the formation of the acetylenic derivative
Vb could be detected (yield 13%) [scheme (3)].
Product
R2Y2
III
IV
V
Ph2S2
1.0 (5%)
1.0 (36%)
1.0 (41%)
1.0 (63%)
–
3.3 (23%)
1.0 (43%)
0.5 (19%)
0.1 (5%)
1.0 (19%)
1.0 (34%)
3.3 (23%)
0.2 (8%)
0.2 (9%)
–
Ph2Sе2
Bn2S2
Bn2Se2
а
Ph2Sе2
3.0 (58%)
0.4 (13%)
BnSe−
− Cl−
SeBn
I
IIIb
IVb
(3)
а
Bn2Se2
1.0 (36%)
Vb
а R2Y2 : KOH = 1 : 10.
The reaction of disulfide IIа with I at –10 to –20°С
results in chloropropenyl derivative IIIa in 60% yield.
Products IVа and Vа were not detected but in the
reaction mixture was found bis(2-chloro-1-propen-3-
yl)sulfide (VI) (yield 7%). Its formation can be due to
sulfide ions S2–, which can be generated upon reductive
splitting of disulfide IIа according to reaction (1). This
process occurs at 85–90°С [1], that is, in the conditions
in which disulfide IIа can be reduced both at the C–S
and the S–S bond [scheme (4)].
Like Ph2S2 [5] and Ph2Sе2 [6], dibenzyldisulfide IIа
with 2,3-dichloro-1-propene (I) in the system
hydrazine hydrate–KOH at 30–35°С (2 h) gives three
products: 2-chloro-3-benzylsulfanyl-1-propene (IIIа)
(yield 41%), 1-benzylsulfanylpropadiene (IVа) (19%)
and 1-benzylsulfanyl-1-propyne (b) (9%). In the same
conditions, dibenzyldiselenide (IIb) affords only two
products: 2-chloro-3-benzylselanyl-1-propene (IIIb)
(63%) and 1-benzylselanylpropadiene (IVb) (5%). The
selenium analog of the acetylene derivative Vа was not
detected in the products of the reaction. The formation
of the above products can be represented by the
sequence of transformations (the domino reaction)
depicted in scheme (2).
Bn–S–S–Bn + N2H4·H2O + 3KOH
→ PhMe + K2S + BnSK + 4H2O,
S
(4)
2I + K2S
Cl
Cl
VI
BnY−
Sulfide VI, apparently, is formed at higher
temperatures, too, (vide supra) but under these condi-
tions it should rapidly suffer further transformations
(dehydrochlorination and resinification or decomposi-
tion of the formed allylic and acetylenic sulfides).
YBn
Cl
− Cl−
Cl
Cl
I
IIIа, IIIb
OH−
Y=S
At 60°С and the ratio Bn2S2 : KOH = 1 : 5 after
19 h two compounds are present in the reaction
products: acetylenic sulfide Vа (yield 58%) and Z-1,2-
bis(benzylsulfanyl)-1-propene VII (yield 36%).
Apparently, under these conditions the domino reac-
tion goes further (as in the case of Ph2S2 [5] and Ph2Se2
[6]) [scheme (5)].
(2)
SBn
YBn
− Cl−, − H2O
IVа, IVb
Y = S (а), Se (b).
Vа
In order to estimate the effect of the nature of the
chalcogen atom and the substituent in the
organylchalcogenide ion on the course of the domino
reaction (2) we have compared the molar ratios of the
products formed under similar conditions from Ph2Y2
and Bn2Y2 (Y = S, Sе) (see table).
Me
H
H2O
(5)
Vа + BnS−
− OH−
SBn
SBn
VII
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SPECIFIC FEATURES OF THE REACTIONS OF 2,3-DICHLORO-1-PROPENE
441
Compound VII is formed selectively as the Z-
isomer, apparently, due to conventional trans-addition
of the nucleophile to the triple bond [9].
graph (column 2000 × 3 mm, liquid phase DC-550, 5%
on Chromaton N-AW-HMDS, linear temperature
programming mode 12 deg/min, gas carrier is helium).
Under the same conditions but for longer duration
of the reaction time (26 h) the acetylenic sulfide Vа
was obtained in 52% yield, and product VII, in 44%
yield.
Reaction of 2,3-dichloro-1-propene (I) with di-
benzyldisulfide IIа. To the solution of 8.0 g (0.014 mol)
KOH in 35 mL of hydrazine hydrate 7.0 g (0.028 mol)
of disulfide IIа was added portionwise at 40–50°С.
The reaction mixture was heated at 85–90°С for 3 h,
cooled to room temperature and 6.31 g (0.057 mol) of
2,3-dichloro-1-propene (I) was added dropwise. The
reaction mixture was stirred for 2.5 h at 25°С, then 2 h
at 30–35°С. After cooling to room temperature the
mixture was extracted with СН2Сl2 (3 × 50 mL), the
combined extracts dried over MgSO4 and the solvent
removed. The residue (7.34 g), from the GC, GC-MS
Vacuum distillation of bissulfide VII results in
partial Z→E isomerization and affords the mixture
containing 65–75% of the Z-isomer VII and 25–35%
of the E–isomer VIIа [Eq. (6)].
Me
SBn
t
(6)
VII
1
H
SBn
and H NMR analysis contains three products (IIIа,
1
VIIа
IVа, and Vа) in the molar ratio (from H NMR)
1.0 : 0.5 : 0.2 (the yields are given in the text).
Proceeding of isomerization [Eq. (6)] in the case of
the benzyl derivative VII (as compared to its absence
in the case of analogous phenyl derivative [5]) can be
due to its higher boiling temperature, that facilitates
the interconversion of the geometric isomers.
2-Chloro-3-benzylsulfanyl-1-propene (IIIа). The
reduction of 7.0 g of disulfide IIа was carried out as
above. The reaction with 2,3-dichloro-1-propene (I)
was performed at –10 to –20°С (10 h). Extraction with
СН2Сl2 removal of solvent afforded 7.2 g of residue
containing 95% (6.84 g) of compound IIIа and 5%
(0.36 g) of bis(2-chloro-1-propene-3-yl)sulfide (VI)
(yields are given in the text). Sulfide IIIа was isolated
by vacuum distillation, bp 89–92°С (1.5 mm Hg). IR
spectrum, ν, cm–1: 3104, 3085, 3062, 3029, 2946,
2916, 1627(С=С), 1601, 1494, 1453, 1407, 1233,
1208, 1115, 1071, 1029, 890, 836, 770, 749, 701, 680,
Dibenzyldiselenide IIb at 60°С after 30 h forms a
complex mixture of products in which it was im-
possible to unambiguously identify 1,2-bis(benzyl-
selanyl)-1-propene.
Therefore, the readily performed reaction of
dibenzyldichalcogenides with 2,3-dichloro-1-propene
allows to prepare unsaturated sulfides and selenides
(including allylic and acetylenic derivatives) possessing
the benzyl group at the heteroatoms.
1
630, 564, 519, 471. Н NMR spectrum, δ, ppm: 3.16 s
(2Н, СН2Ph), 3.65 s (2Н, SCH2CCl=), 5.27 s (2H,
13
CH2=), 7.17–7.26 m (5H, Ph). С NMR spectrum, δС,
EXPERIMENTAL
ppm: 35.23 (СН2Ph), 38.58 (SСН2CCl=), 114.38
(CH2=), 127.05 (Сp), 128.41, 128.93 (Со, Сm), 138.26
(Сi), 137.30 (=CCl–). Mass spectrum, m/z (Irel, %): 198
(4) [M]+·, 123 (4) [BnS]+, 122 (26) [PhCHS]+·, 121 (3)
[PhC≡S+], 92 (6) [PhMe]+·, 91 (33) [C7H7]+, 77 (4)
[Ph]+, 65 (7) [C5H5]+, 45 (5) [HC≡S+]. Found, %: С
60.49; Н 5.51; S 16.15; Cl 17.68. С10Н11SCl. Cal-
culated, %: С 60.44; Н 5.58; S 16.13; Cl 17.84.
IR spectra were registered in thin layer on a Bruker
1
IFS-25 spectrometer. Н, 13С, 77Se NMR spectra were
registered on a Bruker DPX 400 (400.13, 100.62,
76.31 MHz, respectively) in CDCl3 with internal
standards TMS (1Н, 13С), Me2Se (77Se). Mass spectra
were obtained on a Shimadzu GCMS–QP5050A
chromatomass spectrometer (column SPB-5, 60000 ×
0.25 mm), quadruple mass analyzer in the mass range
34-650 Da, electron impact at 70 eV, temperature of
ionic source 190°С. The values of m/z for Se- and Cl-
containing ions are given for 80Se and 35Cl isotopes.
The value of Irel is given taking into account total
intensity for all isotopes.
1-Benzylsulfanylpropadiene (IVа) was obtained
in 19% yield at the temperature of the reaction of 30–
35°С. After vacuum distillation, fraction with bp 90–
1
91°С (2 mm Hg) contain (from Н NMR) 60% of the
allenyl derivative IVа and 40% of compound Vа. IR
1
spectrum, ν, cm–1: 1941 (С=С=С). Н NMR spectrum,
δ, ppm (J, Hz): 3.77 s (2Н, СН2Ph), 4.90 d (2Н,
The reactions were monitored and the liquid
products analyzed on a LKhM 80-MD-2 chromato-
СН2=С=, 3J 6.4 Hz), 5.69 t (1Н, С=С=СН–, 3J 6.4 Hz),
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 84 No. 3 2014

442
LEVANOVA et al.
7.19–7.25 m (5Н, С6Н5). 13С NMR spectrum, δС, ppm:
36.85 (СН2S), 80.19 (СН2=C=), 86.83 (СН=C=),
128.10 (Сp), 128.35, 128.85 (Со, Сm), 137.64 (Сi),
206.28 (=C=). Mass spectrum, m/z (Irel, %): 162 (9)
[М]+·, 161 (3) [М – Н]+, 129 (17) [М – SH]+, 128 (3)
[М – H2S]+·, 91 (49) [C7H7]+, 65 (8) [C5H5]+, 51 (3).
of KOH in 18 mL of hydrazine hydrate 5.0 g
(0.015 mol) of diselenide IIb was added in portions.
The reaction mixture was heated at 85–90°С for 3 h,
cooled to room temperature and added 3.3 g (0.03 mol)
of 2,3-dichloro-1-propene (I) dropwise, stirred for
2.5 h at 25°С, then 2 h at 30–35°С and treated as
above for diphenyldisulfide (IIа). The residue after
removal of solvent (4.83 g) contained, according to the
1-Benzylsulfanyl-1-propyne (Vа) was obtained in
58% yield at the temperature of the reaction of 60°С.
bp 90–91°С (2 mm Hg). IR spectrum, ν, сm–1: 2199
(С≡С). 1Н NMR spectrum, δ, ppm: 1.85 s (3Н,
Ме–С≡), 3.82 s (СН2S), 7.24–7.28 m (Рh). 13С NMR
spectrum, δС, ppm: 4.87 (Ме), 40.01 (SСН2), 67.33
(≡С–S), 91.81 (≡С–Ме), 127.48 (Сp), 127.41, 128.88
(Со, Сm), 136.94 (Сi). Mass spectrum, m/z (Irel, %): 162
(7) [М]+·, 161 (6) [М – Н]+, 129 (15) [М – SH]+, 128
(4) [М – H2S]+·, 92 (3) [C7H8]+·, 91 (42) [C7H7]+, 65 (7)
[C5H5]+, 51 (3). Found, %: С 73.95; Н 6.29; S 19.60.
С10Н10S. Calculated, %: С 74.03; Н 6.21; S 19.76.
1
GC, GC-MS and Н NMR, two products (IIIb and
1
IVb) in the molar ratio (from Н NMR) 1.0 : 0.1 (the
yields are given in the table).
2-Chloro-3-benzylselanyl-1-propene (IIIb) was
isolated by vacuum distillation of the residue. bp 117–
118°С (2 mm Hg). IR spectrum, ν, cm–1: 1624 (С=С).
1Н NMR spectrum, δ, ppm (J, Hz): 3.23 s (2Н, SeСН2–
CCl=, 2JН–С–Se 14.3 Hz), 3.75 s (2Н, SeСН2–Рh, 2JН–С–Se
13.1 Hz), 5.19 d (1Н, –СН=С–С, 2J 1.1 Hz), 5.15–5.20
m (1Н, –СН=С–С), 7.14–7.23 m (5H, Ph). 13С NMR
1
spectrum, δC, ppm (J, Hz): 27.58 (SeСН2CCl=, JС–Se
Bis(2-chloro-1-propen-3-yl)sulfide (VI)
was
1
61.6 Hz), 30.53 (SeСН2–Рh, JС–Se 69.0 Hz), 113.70
isolated by vacuum distillation of the mixture of
products prepared, at the temperature of the reaction of
–10 to –20°С. Boiling point and spectral charac-
teristics coincide with those for the earlier prepared
product [2].
(CH2=), 126.73 (Сp), 128.37, 128.92 (Со, Сm), 138.33
(Сi), 13.43 (–CCl=). 77Se NMR spectrum, δSe, ppm:
295.1. Mass spectrum, m/z (Irel, %): 246 (9) [M]+·, 170
(10) [PhCHSе]+·, 92 (6) [C7H8]+, 92 (60) [C7H7]+, 65
(5) [C5H5]+. Found, %: С 49.13; Н 4.48; Sе 32.04; Cl
14.43. С10Н11SеCl. Calculated, %: С 48.90; Н 4.51; Sе
32.15; Cl 14.43.
Z-1,2-Bis(benzylsulfanyl)-1-propene (VII) was
prepared in 36–44% yield at the temperature of the
reaction of 60°С. IR spectrum, ν, cm–1: 1627 (С=С).
1Н NMR spectrum, δ, ppm: 1.83 s (3Н, Ме), 3.76 s,
3.86 s (4Н, СН2Ph), 5.90 s (1Н, =С–Н), 7.14–7.26 m
(Рh). 13С NMR spectrum, δC, ppm: 23.90 (Ме), 35.67,
37.96 (СН2Рh), 124.61 (=С–Н); it is difficult to
unambiguously assign the 13С signals of the Ме–С=
group and benzene rings in the range 127.04–
138.15 ppm. Mass spectrum, m/z (Irel, %): 286 (21) [М]+·,
195 (3) [М – Bz]+, 92 (4) [C7H8]+·, 91 (56) [C7H7]+,
65 (6) [C5H5]+. Found, %: С 71.06; Н 6.26; S 22.27.
С17Н18S2. Calculated, %: С 71.28; Н 6.33; S 22.38.
1-Benzylselanylpropadiene (IVb) was isolated as
a mixture with 1-benzylselanyl-1-propyne (Vb) by
distillation. Fraction with bp. 110–112°С (2 mm Hg)
contained 45% of compound IVb. Selenide IVb: IR
1
spectrum, ν, cm–1: 1942 (С=С=С). Н NMR spectrum,
δ, ppm (J, Hz): 3.83 s (2Н, SeСН2Ph, 2JН–С–Se 11.6 Hz),
4
4.68 d (2Н, СН2=С=С, JН–Н 6.4 Hz), 5.78 t (1Н,
SeСН=С=С, 4JН–Н 6.4 Hz), 7.14–7.23 m (5Н, Рh). 13С
NMR spectrum, δC, ppm (J, Hz): 29.88 (SeСН2Ph,
1
1JС–Se 60.0 Hz), 76.37 SeСН=С=С, JС–Se 110.8 Hz),
77.46 (СН2=C=С), 126.76 (Сp), 128.32, 128.85 (Со,
Сm), 138.27 (Сi), 205.77 (=C=). 77Se NMR spectrum,
δSe, ppm: 294.7. Mass spectrum, m/z (Irel, %): 210 (6)
[М]+·, 129 (25) [М – SeH]+, 117 (5) [М – CHSe]+, 92
(2) [C7H8]+, 91 (55) [C7H7]+, 65 (9) [C5H5]+.
E-1,2-Bis(benzylsulfanyl)-1-propene (VIIа). Dis-
tillation of compound VII [bp 210–217 °С (2 mm Hg)]
gave two products (1Н, 13С and GC-MS data). For
1
compound VIIа: Н NMR spectrum, δ, ppm: 1.87 s
(3Н, Ме), 3.67 s, 3.75 s (4Н, СН2Ph), 5.79 s (1Н,
=С–Н), 7.14–7.26 m (Рh). 13С NMR spectrum, δC,
ppm: 19.70 (Ме), 36.72, 38.21 (СН2–Рh), other signals
could not be identified. The mass spectrum is similar
to that of the Z-isomer of VII.
1
1-Benzylselanyl-1-propyne (Vb). Н NMR spec-
trum, δC, ppm (J, Hz): 1.89 s (3Н, Ме), 3.91 s (2Н,
SeСН2Рh, 2JН–С–Se 13.6 Hz), 7.14–7.23 m (5Н, Рh). 13С
NMR spectrum, δC, ppm (J, Hz): 5.18 (Ме), 32.16
1
(SеСН2Рh, JС–Se 54.3 Hz), 58.32 (SеС≡С), 97.38
Reaction of 2,3-dichloro-1-propene (I) with di-
benzyldiselenide IIb. To the solution of 4.1 g (0.07 mol)
(Ме–С≡), 127.17 (Сp), 128.31, 128.71 (Со, Сm), 137.65
(Сi). 77Se NMR spectrum, δSe, ppm: 241.7. Mass
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SPECIFIC FEATURES OF THE REACTIONS OF 2,3-DICHLORO-1-PROPENE
443
spectrum, m/z (Irel, %): 210 (8) [М]+·, 129 (25) [М –
SeН]+, 92 (3) [C7H8]+·, 91 (54) [C7H7]+, 65 (9) [C5H5]+.
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