Chalcogenation of 1,4-dichlorobut-2-yne with organic dichalcogenides in the system hydrazine hydrate–KOH

Article abstract of DOI:10.1007/s11172-015-1121-1

A reaction of organic dichalcogenides R₂Y₂ (R = Ph, Bn, Pr; Y = S, Se) with 1,4-dichlorobut-2-yne in the system hydrazine hydrate–KOH leads to four principal products: 1,4-bis(organylchalcogenyl)but-2-ynes, 1-organylchalcogenylbut-1-en-3-ynes, 4-organylchalcogenylbut-1-en-3-ynes, and 3(5)-methylpyrazole. The selectivity of the formation of individual products is determined by the ratio of the substrates used and the reaction temperature. A plausible mechanism of chalcogenation considered in the work agrees with the effect of the nature of chalcogene atoms and organic substituents R on stability of intermediates and products. The stabilization of carbanions by α chalcogene-containing groups corresponds to the following order: PhS > PhSe > BnS > BnSe > PrS.

Full text of DOI:10.1007/s11172-015-1121-1

Russian Chemical Bulletin, International Edition, Vol. 64, No. 9, pp. 2083—2089, September, 2015
2083
Chalcogenation of 1,4ꢀdichlorobutꢀ2ꢀyne
with organic dichalcogenides in the system hydrazine hydrate—KOH*
E. P. Levanova, V. S. Vakhrina, V. A. Grabel´nykh, I. B. Rozentsveig, N. V. Russavskaya,
A. I. Albanov, L. V. Klyba, and N. A. Korchevin
A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences,
1 ul. Favorskogo, 664033 Irkutsk, Russian Federation.
Fax: +7 (395 2) 41 9346. Eꢀmail: venk@irioch.irk.ru
A reaction of organic dichalcogenides R2Y2 (R = Ph, Bn, Pr; Y = S, Se) with 1,4ꢀdichloroꢀ
butꢀ2ꢀyne in the system hydrazine hydrate—KOH leads to four principal products: 1,4ꢀbisꢀ
(organylchalcogenyl)butꢀ2ꢀynes, 1ꢀorganylchalcogenylbutꢀ1ꢀenꢀ3ꢀynes, 4ꢀorganylchalcogenylꢀ
butꢀ1ꢀenꢀ3ꢀynes, and 3(5)ꢀmethylpyrazole. The selectivity of the formation of individual prodꢀ
ucts is determined by the ratio of the substrates used and the reaction temperature. A plausible
mechanism of chalcogenation considered in the work agrees with the effect of the nature of
chalcogene atoms and organic substituents R on stability of intermediates and products. The
stabilization of carbanions by α chalcogeneꢀcontaining groups corresponds to the following
order: PhS > PhSe > BnS > BnSe > PrS.
Key words: 1,4ꢀdichlorobutꢀ2ꢀyne, chalcogenation, chalcogeneꢀcontaining nucleophiles,
carbanions, stabilization, disulfides, diselenides.
A high and versatile reactivity of unsaturated orgaꢀ
nochalcogene compounds determines their important role
in organic synthesis.1,2 In turn, the preparation of unsatꢀ
urated sulfides and selenides, as well as other types of
chalcogeneꢀcontaining compounds is largely based on
treatment of unsaturated electrophilic substrates with chalꢀ
cogenide nucleophilic agents.
Commercially available 1,4ꢀdichlorobutꢀ2ꢀyne (1) is
an important substrate in the synthesis of highly unsaturꢀ
ated systems. Depending on the character of acting nucleoꢀ
phile, which can direct its attack either on the carbon
atom in the sp3ꢀhybridization (SNC, a classic SN2 nucleoꢀ
philic substitution), or on the chlorine atom (SNCl,
dechlorination), or on the hydrogen atom (SNH, deꢀ
hydrochlorination), both the composition and the strucꢀ
ture of the reaction products can substantially differ. In
general case, the possibility for nucleophilic reactions to
follow different pathways is discussed in detail in the literꢀ
ature, in particular, the principal features and synthetic
application of the SNClꢀtype reactions for different subꢀ
strates are reviewed.3 Nevertheless, for the chalcogeneꢀ
containing nucleophiles these processes are not studied
deeply enough with respect to some electrophiles, in parꢀ
ticular, to 1,4ꢀdichlorobutꢀ2ꢀyne (1).
double dehydrochlorination, giving rise to diacetylene in
95—98% yield.4 However, in most cases studied the reacꢀ
tions of diacetylene4—6 or 1,4ꢀdichlorobutyne 17—9 with
chalcogeneꢀcontaining nucleophiles led to different prodꢀ
ucts. The reactions of diacetylene with thiolates gave the
antiꢀMarkovnikov products of nucleophilic addition of the
RS– anions to one triple bond, i.e., butenyne derivatives.5,6
The scarce data7—9 on the reactions of 1,4ꢀdichlorobutꢀ2ꢀ
yne with chalcogeneꢀcontaining nucleophiles are contraꢀ
dictory. The reactions with thiolate 2a or selenolate 2b,
which were obtained by treatment of thioꢀ or selenophenol
with metallic sodium upon reflux of the reaction mixture
for 4.5 h, gave 1,4ꢀbis(phenylchalcogenyl)butꢀ2ꢀynes 3a,b
in 74% and 65% yield, respectively7. However, when the
reaction of dichlorobutyne 1 with thiophenol was carried
out in the presence of triethylamine in CH2Cl2, it gave,
together with compound 3a (up to 29% yield), the monoꢀ
8
≡
substitution product ClCH2C CCH2SPh (30—62% yield).
Similar product was obtained in 50% yield from thiophenol
and dichlorobutyne 1 under heterophase conditions.9
In the present work, we report our results on chalcoꢀ
genation of dichlorobutyne 1 with organic dichalcogenides
in the system hydrazine hydrate—KOH. Note that preꢀ
parative handling of organic dichalcogenides R2Y2 is more
convenient than that of the corresponding thiols and espeꢀ
cially selenols.
Compound 1 treated with hard nucleophiles, for exꢀ
ample, alcoholic solutions of alkalis, undergoes selective
The reducing system hydrazine hydrate—KOH is
well proven for the synthesis and studies of reactivity of
organochalcogene compounds.10,11 In this system, dichalꢀ
* Dedicated to Academician of the Russian Academy of Sciences
N. S. Zefirov on the occasion of his 80th birthday.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 2083—2089, September, 2015.
1066ꢀ5285/15/6409ꢀ2083 © 2015 Springer Science+Business Media, Inc.

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Levanova et al.
cogenides are preliminary converted to chalcogenolatꢀ
es 2a—e. The dichalcogenides are activated according to
Scheme 1.
enced the most the ratio of products 3—6. The ratio of
reactants R2Y2 : KOH = 1 : 2 provided the most selective
formation of bischalcogenides 3. Raising in the amount of
KOH to the ratio R2Y2 : KOH = 1 : 5, commonly used for
the reducing activation of dichalcogenides,11 caused rise
of the fraction of products 4 and 5, whose yields considerꢀ
ably depended on the reaction temperature. The elevated
temperature favored the formation of chalcogenide 4 with
the terminal acetylene group. At 0 °C or 30—35 °C, chalꢀ
cogenide 5 with the internal triple bond was formed in up
to 37% yield (for PhSK). These facts allow us to draw
a conclusion that chalcogenides 4 are thermodynamically
controlled products, whereas products 5 are kinetically
controlled.
Taking into account that the reaction of diacetylene
with chalcogeneꢀcontaining nucleophiles first of all leads
to ethynylvinyl derivatives,1—3 it can be suggested that the
formation of products 3—5 is not related to a possible
intermediate generation of diacetylene from dichloroꢀ
butyne 1, it rather occurs by means of nucleophilic substiꢀ
tution of the chlorine atom and dehydrochlorination. The
formation of products 3—5 is represented in Scheme 4.
A classic nucleophilic substitution of one chlorine atom
in compound 1 with a chalcogenide anion gives the interꢀ
mediate product 7. As it was mentioned above, a comꢀ
pound of the type 7 (RY = PhS) has been described in the
literature.8,9 It was obtained upon treatment of dichloꢀ
Scheme 1
a
Ph
S
b
Ph
Se
c
Bn
S
d
Bn
Se
e
Pr
S
R
Y
The process is carried out in hydrazine hydrate, which
prevents reꢀoxidation of RY– anions with air oxygen.
Chalcogenolates 2a—e were used in the reaction with
1,4ꢀdichlorobutꢀ2ꢀyne (1) without isolation in the indiꢀ
vidual state.
The addition of 1,4ꢀdichlorobutꢀ2ꢀyne (1) to a soluꢀ
tion of chalcogenolate 2a—e led to four types of products,
the ratio of which depended on the nature of agent RY–
and reaction conditions: 1,4ꢀbis(organylchalcogenyl)butꢀ
2ꢀynes (3), 1ꢀorganylchalcogenylbutꢀ1ꢀenꢀ3ꢀynes (4),
4ꢀorganylchalcogenylbutꢀ1ꢀenꢀ3ꢀynes (5), and 3(5)ꢀmeꢀ
thylpyrazole (6) (Schemes 2 and 3, Table 1).
As it is seen from the Table, the amount of the alkali
used for the reducing cleavage of dichalcogenides influꢀ
Scheme 2
Scheme 3
Scheme 4

Chalcogenation of 1,4ꢀdichlorobutꢀ2ꢀyne
Russ.Chem.Bull., Int.Ed., Vol. 64, No. 9, September, 2015 2085
Table 1. Reaction conditions, composition and yield of products 3—6 in the chalcogenation reaction of 1,4ꢀdichlorobutꢀ
2ꢀyne (1) with organic dichalcogenides
Entry
R2Y2
Ratio of reagents
t/°C
τ/h
Yield (%)
R2Y2 : KOH R2Y2 : 1
3
4
5
6
1
Ph2S2
1 : 2
1 : 1
25,
30—35a
0
25,
30—35
25,
30—35
60
60
2.5,
2
11
2.5,
2
2.5,
2
78
—
—
—
2
3
Ph2S2
Ph2S2
1 : 5
1 : 5
1 : 2
1 : 2
14
20
18
46
37
—
14
15
12
—
4
Ph2S2
1 : 5
1 : 1
—
60
25
21
5
6
Ph2S2
Ph2S2
1 : 5
1 : 5
1 : 2
1 : 1
5
19
Traces
54
Unidentified mixture
of products
7
8
Ph2Se2
Ph2Se2
1 : 2
1 : 2
1 : 1
1 : 2
25,
30—35
25,
30—35
0
25,
30—35
60
25,
30—35
25,
30—35
60
25,
30—35
25,
30—35
10
25
25,
2.5,
2
2.5,
2
11
2.5,
2
5
2.5,
2
2.5,
2
5
2.5,
2
2.5,
2
2.5
3.5
2.5,
2
98
99
—
—
—
—
—
—
9
10
Ph2Se2
Ph2Se2
1 : 5
1 : 5
1 : 2
1 : 2
35
19
20
24
12
13
14
14
11
12
Ph2Se2
Bn2S2
1 : 5
1 : 2
1 : 2
1 : 1
33
95b
20
—
12
—
29
—
13
Bn2S2
1 : 5
1 : 2
25
25
19
21
14
15
Bn2S2
Bn2Se2
1 : 5
1 : 2
1 : 2
1 : 1
25
92
27
—
16
—
28
—
16
17
18
19
Bn2Se2
Pr2S2
Pr2S2
Pr2S2
1 : 5
1 : 5
1 : 5
1 : 5
1 : 2
1 : 2
1 : 2
1 : 2
31c
77
60
99
8.5
12
15
—
15
—
13
—
12
13
16
—
30—35
60
5
a The reaction mixture was stirred 2.5 h at 25 °C and 2 h at 30—35 °C.
b 2—3% of benzalazine 8 was formed.
c The yield is calculated on the amount of dichlorobutyne 1 taken for the reaction, the yield on dibenzyl diselenide was 87%.
robutꢀ2ꢀyne 1 with a half equivalent of thiophenol in the
presence of triethylamine. However, we failed to isolate
compound 7 in the system hydrazine hydrate—KOH,
direction of the process is determined by the stability of
carbanion A, which, in turn, is determined by the nature
of chalcogene Y and the electron effects of the R group.
Further transformations of carbanion A include the elimiꢀ
nation of Cl– anion (step c), which, apparently, goes
through the formation of the intermediate cumulene prodꢀ
uct B. The high reactivity of cumulenes12 in the presence
of bases provokes an alleneꢀacetylene rearrangement.13
The nonsymmetricity of molecule B predetermines a posꢀ
sibility of the alleneꢀacetylene rearrangement in two diꢀ
rections (d and e) with the formation of compounds 4 and 5.
As it has been already mentioned, chalcogenides 4 with
the terminal acetylene group under the reaction condiꢀ
tions are thermodynamically more stable than compounds 5,
though this statement requires a detailed quantum chemiꢀ
1
though the H NMR spectra of the mixture of products
formed at the ratio of reagents R2Y2 : 1 = 1 : 5 confirmed
a possibility of the formation of monochalcogenide 7.
When there is no excess of the alkali, compounds 7
undergo further nucleophilic substitution with the formaꢀ
tion of products 3 in the yields close to quantitative (pathꢀ
way a in Scheme 4). However, dehydrochlorination of
compounds 7 is possible in the presence of excessive alkali,
which occurs through the intermediate formation of carꢀ
banion A stabilized by both the electronꢀwithdrawing
acetylene fragment and the chalcogene atom of the RY
group (pathway b in Scheme 4). It is obvious that this

2086
Russ.Chem.Bull., Int.Ed., Vol. 64, No. 9, September, 2015
Levanova et al.
cal confirmation. It should be noted that compounds 5a,b,e
described in the literature were obtained not from diacetylꢀ
ene, but indirectly from vinylacetylene organometallic deꢀ
rivatives and the corresponding organylchalcogenyl chloꢀ
rides.14,15
from compound 1 and thiourea19 in 87% yield (Scheme 6).
When preparing compounds 3c,e, the system hydrazine
hydrate—KOH was slowly added to the mixture of salt 9
and the corresponding alkylating agent (BnCl or PrBr) in
order to avoid the contact of salt 9 with an excess of the
alkali according to the data in the work.20
1
Judging from the H NMR spectroscopy data, most
likely compounds 4 are exclusively formed as Zꢀisomers,
3
since the constant JH,H in the vinyl fragment has only
one value and is equal to 9.7—9.9 Hz.
Scheme 6
A possibility of transformations shown in Scheme 3 is
determined by the stability of carbanions located at
αꢀposition to the chalcogene atom. Taking into account
the data in the works,11,16 which deal with the evaluation
of the effect of a chalcogenyl substituent on the neighꢀ
boring carbanionic center, the probability of the reaction
taking pathway b (Scheme 4) should correspond to the
following order: PhS– > PhSe– > BnS– > BnSe– > PrS–,
that is in good agreement with the freshly obtained data
(see Table 1).
Running the reaction given in Schemes 2 and 3 at
60 °C shows that, with the ratio R2Y2 : KOH = 1 : 5 being
the same, the choice of the pathways a or b (see Scheme 4)
for different R2Y2 is subject to the same rules: while bissulꢀ
fide 3a is completely absent for Ph2S2, for Pr2S2 product 3e
forms in virtually quantitative yield.
3ꢀMethylpyrazole 6 is formed in the reaction of 1,4ꢀdiꢀ
chlorobutꢀ2ꢀyne 1 with hydrazine (Scheme 3), which we
demonstrated earlier in the independent experiments.17
Its yield increases as the concentration of the chalcoꢀ
genating agent in the reaction mixture decreases (entry 4)
or the temperature of the process increases to 60 °C (see
entries 5, 11, and 14). It is formed even if the chalcogeꢀ
nating agent has a decreased reactivity, when a competꢀ
ing reaction of dichlorobutyne 1 with hydrazine becomes
possible.
i. 2 BnCl, N2H4•H2O/KOH (– 2 KCl, – CO2, – 2 NH3)
ii. 2 PrBr, N2H4•H2O/KOH (– 2 KBr, – CO2, – 2 NH3)
In conclusion, a preparatively easily feasible reaction
of 1,4ꢀdichlorobutꢀ2ꢀyne 1 with organic dichalcogenides
in the hydrazine hydrate—KOH system can be considered
as an approach to highly unsaturated organochalcogene
compounds: 1,4ꢀdichalcogenylbutꢀ2ꢀynes, chalcogenylꢀ
butenynes, and chalcogenylbutynenes. The consideration
of the mechanisms of transformations taking place in the
reaction allows one to evaluate the effects of the chalcoꢀ
gene agent nature on the character of the products formed.
Compounds 3a—e were isolated in the individual state
and characterized by spectroscopic methods. The prodꢀ
ucts 4 and 5 were identified only in the mixture, using 1H,
13C, and 77Se NMR spectroscopy, GLCꢀMS, and IR
spectroscopy.
The use of dibenzyl disulfide and low concentrations
of KOH (the ratio Bn2S2 : KOH = 1 : 2) and 1,4ꢀdichloroꢀ
butꢀ2ꢀyne 1 (Bn2S2 : 1 = 1 : 1) leads, apart from product
3c (95% yield), also to benzalazine 8 in 2—3% yield (idenꢀ
tified by NMR spectroscopy and GLCꢀMS), which is
formed in the reaction of dibenzyl disulfide with hydrꢀ
azine18 (Scheme 5).
Experimental
Monitoring of the purity of the starting 1,4ꢀdichlorobutꢀ2ꢀ
yne and analysis of reaction products were carried out on a LKhM
80ꢀMDꢀ2 chromatograph (a 2000×3ꢀmm column, liquid phase
Silicon XEꢀ60, 5% on Chromaton NꢀAWꢀHMDS, the column
temperatures was linearly programmed from 30 to 230 °C at the
rate of 12 deg min–1, carrier gas helium). 1H, 13C, and 77Se
NMR spectra were recorded on a Bruker DPXꢀ400 spectroꢀ
meter (400.13 (1H), 100.61 (13C), and 76.31 MHz (77Se)) in
solutions in CDCl3, using TMS as an internal standard [(CH3)2Se
for 77Se].
Scheme 5
Mass spectra were obtained on a Shimadzu GCMSꢀQP5050A
chromatoꢀmass spectrometer (a SPBꢀ5 column, 60000×0.25 mm),
the film thickness of the stationary phase 0.25 μm; injector temꢀ
perature 250 °C, carrier gas helium, the flow rate 0.7 mL min–1
,
The sulfurꢀcontaining products 3c,e were obtained in
91—92% yield by an alternative synthesis using a double
isothiuronium salt 9, S,S´ꢀ(butꢀ2ꢀynꢀ1,4ꢀdiyl)bis(isoꢀ
thiuronium) dichloride, which, in turn, was synthesized
the programmed elevation of temperature from 60 to 260 °C at
the rate of 15 deg min–1. The temperature of detector 250 °C,
a quadrupole mass analyzer, electron ionization with energy of
electrons 70 eV, the temperature of the source of ions 200 °C, the

Chalcogenation of 1,4ꢀdichlorobutꢀ2ꢀyne
Russ.Chem.Bull., Int.Ed., Vol. 64, No. 9, September, 2015 2087
range of the detected masses 34—650 Da. The m/z values for the
seleniumꢀcontaining ions are reported for the 80Se isotope, the
relative intensity was calculated with allowance for the signals
from all the isotopes.
Elemental analysis for selenium in seleniumꢀcontaining comꢀ
pounds was carried out by burning of the sample in oxygen atmoꢀ
sphere and reduction of the selenious acid formed with potasꢀ
sium iodide.21 The liberated iodine was titrated with a solution
of sodium thiosulfate in the presence of starch.
1,4ꢀDichlorobutꢀ2ꢀyne (1) was synthesized from the indusꢀ
trial product butꢀ2ꢀyneꢀ1,4ꢀdiol and thionyl chloride according
to the known procedure.4 Diphenyl disulfide, diphenyl diseꢀ
lenide, dibenzyl disulfide are commercially available reagents.
Dipropyl disulfide and dibenzyl diselenide were obtained by the
methods described in the literature.10
and benzalazine 8 (0.11 g). The yield of compound 3c was 95%.
IR, ν/cm–1: 2227 weak (C≡C). 1H NMR, δ: 3.11 (4 H, CH2—C≡);
3.85 (4 H, PhCH2); 7.19—7.32 (m, 10 H, Ar—H). 13C NMR,
δ: 18.9 (CH2—C≡); 35.4 (PhCH2); 79.0 (C≡); 127.1 (Cp); 128.5
(Co), 128.9 (Cm); 137.5 (Cipso). MS, m/z (Irel (%)): 298 [M]+
•
(traces), 207 [M – PhCH2]+ (7), 175 [M – PhCH2S]+ (12), 123
[PhCH2S]+ (10), 91 [PhCH2]+ (51), 77 [C6H5]+ (4), 65 [C5H5]+
(8), 51 [C4H3]+ (4).
B. Synthesis of compound 3c using isothiuronium salt 9.
1. Synthesis of isothiuronium salt 9.19 A mixture of dichloꢀ
robutyne 1 (6.15 g, 0.05 mol) and thiourea (7.6 g, 0.1 mol) was
refluxed for 10 h in ethyl alcohol (60 mL). A white precipitate
formed (10.3 g, 75%) was filtered. M.p. 173—175 °C (decomp.p.
178 °C, Ref. 19: m.p. 182—183 °C with decomp.). 1H NMR, δ:
4.02 (s, 4 H, CH2S); 4.71 (s, 8 H, NH2). 13C NMR, δ: 19.7
(SCH2); 78.1 (–C≡); 169.8 (SC(NH2)2).
Reaction of diorganyl dichalcogenides with 1,4ꢀdichlorobutꢀ2ꢀ
yne (1) (general procedure). A calculated amount of dichalcoꢀ
genide (for the ratio of reagents, see Table 1) was added to
a solution prepared from KOH and hydrazine hydrate. The reꢀ
action mixture was heated for 3 h at 85—90 °C, cooled to the
temperatures indicated in Table 1, followed by a dropwise addiꢀ
tion of a calculated amount of dichlorobutyne 1. After the reacꢀ
tion reached completion (see Table 1), the mixture was brought
to room temperature (25 °C) and extracted with dichloromethane
(3×50 mL). The extract was dried with MgSO4, the solvent was
evaporated. The residue was analyzed by GLC, chromatoꢀmass
spectrometry, NMR, and subjected to vacuum distillation.
1,4ꢀBis(phenylsulfanyl)butꢀ2ꢀyne (3a). Compound 3a was
obtained as indicated above (see Table 1, entry 1) from diphenyl
disulfide (5.46 g, 0.025 mol), KOH (2.81 g, 0.05 mol), and comꢀ
pound 1 (3.08 g, 0.025 mol) in hydrazine hydrate (15 mL). The
yield was 78%, m.p. 41—42 °C (Ref. 8: m.p. 164—165 °C, no
spectral characteristics are given). IR, ν/cm–1: 2257 weak (C≡C).
1H NMR, δ: 3.54 (s, 4 H, CH2S); 7.16—7.33 (m, 10 H, CAr—H).
13C NMR, δ: 22.9 (CH2S); 77.2 (C≡); 125.9 (Cp); 128.9, 129.8
2. Synthesis of bissulfide 3c. A solution of KOH (2.45 g,
0.044 mol) in hydrazine hydrate (10 mL) was added dropwise to
a mixture of isothiuronium salt 9 (3.0 g, 0.011 mol) and benzyl
chloride (2.76 g, 0.022 mol) at 15—20 °C. The resulting mixture was
stirred for 12 h at this temperature and extracted with CH2Cl2.
Pure product 3c (3.0 g, 92%) was obtained after evaporation of
the solvent. M.p. 33—34 °C (from methanol). The spectral charꢀ
acteristics are completely identical to those reported above.
1,4ꢀBis(benzylselanyl)butꢀ2ꢀyne (3d). Bisselenide 3d was obꢀ
tained as indicated above (see Table 1, entry 15) from dibenzyl
diselenide (1.0 g, 0.003 mol), KOH (0.34 g, 0.006 mol), 1,4ꢀdiꢀ
chlorobutꢀ2ꢀyne 1 (0.36 g, 0.003 mol) in hydrazine hydrate
(2 mL). The yield was 1.06 g (92%). A dark red liquid. IR, ν/cm–1
:
1
2226 weak (C≡C). H NMR, δ: 3.07 (s, 4 H, SeCH2—C≡); 3.91
(s, 4 H, PhCH2Se); 7.13—7.28 (m, 10 H, Ar—H). 13C NMR,
δ: 8.0 (SeCH2C≡, JC,Se = 63.3 Hz); 27.4 (PhCH2Se, JC,Se
=
= 60.6 Hz); 80.2 (—C≡); 126.7 (Cp); 128.4 (Co), 128.8 (Cm);
138.6 (Cipso). 77Se NMR, δ: 349.3 (quint, 2JSe,H = 14.2 Hz). MS,
m/z (Irel (%)): a molecular ion peak is absent, 262 [Bn2Se]+
•
(Co, Cm); 135.2 (Cipso). MS, m/z (Irel (%)): 270 [M]+ (7), 161
(16), 171 [BnSe]+ (4), 91 [PhCH2]+ (68), 65 [C5H5]+ (10), 51
[C4H3]+ (2). Found (%): C, 55.28; H, 4.82; Se, 39.84. C18H18Se2.
Calculated (%): C, 55.10; H, 4.59; Se, 40.31.
•
[M – PhS]+ (17), 160 [M – PhSH]+ (9), 128 [C10H8]+ (21),
127 [C10H7]+ (2), 117 [C9H9]+ (3), 115 [C9H7]+ (4), 109
[C6H5S]+ (10), 77 [C6H5]+ (3), 65 [C5H5]+ (6). Found (%):
C, 70.91; H, 5.18; S, 23.95. C16H14S2. Calculated (%): C, 71.07;
H, 5.22; S, 23.71.
•
•
1,4ꢀBis(propylsulfanyl)butꢀ2ꢀyne (3e). A. The product 3e in
the highest yield was obtained from dipropyl disulfide (3.17 g,
0.021 mol), KOH (5.91 g, 0.105 mol), and dichlorobutyne 1
(5.18 g, 0.042 mol) in hydrazine hydrate (26 mL) at 60 °C (see
Table 1, entry 19). The yield was 4.22 g (99%). B.p. 133—135 °C
(3 Torr). IR, ν/cm–1: 2226 weak (C≡C). 1H NMR, δ: 0.99
(t, 3 H, CH3CH2CH2); 1.64 (m, 2 H, CCH2C); 2.62 (t, 2 H,
SCH2CH2CH3); 3.27 (s, 2 H, SCH2C≡). 13C NMR, δ: 13.4
(CH3CH2CH2); 19.6 (SCH2C≡C); 22.3 (CH2CH2CH3); 33.6
(SCH2Et); 78.7 (—C≡). MS, m/z (Irel (%)): 202 [M]+• (15), 160
1,4ꢀBis(phenylselanyl)butꢀ2ꢀyne (3b). Compound 3b was obꢀ
tained similarly (see Table 1, entry 7) from Ph2Se2 (4.0 g,
0.0128 mol), KOH (1.44 g, 0.0256 mol), compound 1 (1.58 g,
0.0128 mol) in hydrazine hydrate (7 mL). The yield was 4.63 g
(99%). M.p. 27—28 °C (from methanol). IR, ν/cm–1: 2225 weak
1
(C≡C). H NMR, δ: 3.45 (s, 4 H, CH2Se); 7.20—7.48 (m, 6 H,
CAr—Ho,p); 7.49—7.51 (m, 4 H, CAr—Hm). 13C NMR, δ: 13.2
(CH2Se, JC,Se = 61.8 Hz); 80.5 (C≡); 127.4 (Cp); 129.0 (Co);
129.8 (Cipso); 133.1 (Cm). 77Se NMR, δ: 376.5. MS, m/z
[M – C3H7]+ (4), 128 [C10H8]+ (5), 117 [C9H9]+ (3), 111
•
•
[C6H7S]+ (5), 86 [Pr – Pr]+• (9), 85 [C6H13
]
+ (9), 84 [C6H12
]
+
•
(Irel (%)): 366 [M]+• (3), 314 [Ph2Se2]+• (11), 234 [M – Ph2Se]+
(3), 77 [C3H9S]+ (2), 71 [C5H11
]
(3), 52 [C4H4]+ (4), 51
+
•
•
(3), 209 [M – PhSe]+ (8), 157 [PhSe]+ (24), 129 [C10H9]+ (7),
128 [C10H8]+ (18), 117 [C9H9]+ (1), 115 [C9H7]+ (2), 78
[C4H3]+ (2). Found (%): C, 59.45; H, 8.86; S, 31.27. C10H18S2.
Calculated (%): C, 59.41; H, 8.91; S, 31.68.
•
[C6H6]+• (5), 77 [C6H5]+ (10), 65 [C5H5]+ (2), 51 [C4H3]+ (8).
Found (%): C, 52.86; H, 4.15; Se, 43.16. C16H14Se2. Calculatꢀ
ed (%): C, 52.77; H, 3.87; Se, 43.36.
1,4ꢀBis(benzylsulfanyl)butꢀ2ꢀyne (3c). A. The residue (4.11 g,
obtained as described above (see Table 1, entry 12) from dibenzꢀ
yl disulfide (3.5 g, 0.0142 mol), KOH (1.59 g, 0.0284 mol), and
dichlorobutyne 1 (1.75 g, 0.0142 mol) in hydrazine hydrate
(7 mL)) contained according to the 1H NMR compound 3c (4.0 g)
B. A solution of KOH (2.45 g, 0.044 mol ) in hydrazine
hydrate (10 mL) was added dropwise to a mixture of isothiuroꢀ
nium salt 9 (3.0 g, 0.011 mol) and propyl bromide (2.68 g,
0.022 mol) at 15—20 °C. The reaction mixture was stirred at this
temperature for 12 h and extracted with dichloromethane
(3×50 mL). Compound 3e (2.0 g, 91%) was obtained after evapꢀ
oration of the solvent. The spectral characteristics are completeꢀ
ly identical to those reported above.

2088
Russ.Chem.Bull., Int.Ed., Vol. 64, No. 9, September, 2015
Levanova et al.
1ꢀPhenylsulfanylbutꢀ1ꢀenꢀ3ꢀyne (4a) (identified in the mixꢀ
ture with compound 5a). Compound 4a was obtained in the
highest yield (60%) (see Table 1, entry 4) from Ph2S2 (5.46 g,
0.025 mol), KOH (7.0 g, 0.125 mol), and dichlorobutyne 1 (3.07 g,
0.025 mol) in hydrazine hydrate (30 mL). The reaction mixture
was allowed to stand for 2.5 h at 25 °C and 2 h at 30—35 °C. After
vacuum distillation of the residue, the fraction with b.p. 81—83 °C
(2 Torr) contained a mixture of compounds 4a and 5a in the
ratio of ~5 : 1. IR, ν/cm–1: 3287 (H—C≡), 2091 (C≡C). 1H NMR,
δ: 3.40 (d, 1 H, HC≡, 4JH,H = 2.3 Hz); 5.54 (dd, 1 H, =CH—C≡,
atoms of the aromatic ring are in the range 128.6—133.1 ppm.
MS, m/z (Irel (%)): 222 [M]+ (12), 141 [M – SeH]+ (9), 91
•
[PhCH2]+ (64), 65 [C5H5]+ (10), 51 [C4H3]+ (7).
1ꢀPropylsulfanylbutꢀ1ꢀenꢀ3ꢀyne (4e) (identified in the mixꢀ
ture with other reaction products). The product 4e was obtained
in the highest yield of 15% (see Table 1, entry 18) from dipropyl
disulfide (4.0 g, 0.027 mol), KOH (7.5 g, 0.135 mol), and dichloꢀ
robutyne 1 (6.54 g, 0.054 mol) in hydrazine hydrate (33 mL).
The reaction mixture was stirred for 2.5 h at 25 °C and 2 h at
1
30—35 °C. IR, ν/cm–1: 3284 (HC≡), 2091 (C≡C). H NMR, δ:
3JH,H = 9.9 Hz, 4JH,H = 2.3 Hz); 6.73 (d, 1 H, =CH—S, 3JH,H
=
1.04 (overlapped with signals of the CH3 groups of other prodꢀ
ucts; m, 3 H, CH3); 1.54 (m, 2 H, SCH2CH3); 2.82 (t, 2 H,
SCH2CH2CH3); 3.43 (s, 1 H, HC≡); 5.50 (d, 1 H, =CH—C≡,
3JH,H = 9.8 Hz); 6.62 (d, 1 H, =CH—S, 3JH,H = 9.8 Hz). 13C NMR,
δ: 13.0 (CH3CH2CH2); 23.7 (CH3CH2); 35.8 (SCH2CH2CH3);
89.5 (C≡C); 103.4 (—CH—C≡); 142.4 (=CHSPr). MS, m/z
(Irel (%)): 126 [M]+• (22), 111 [M – CH3]+ (2), 85 [C4H5S]+ (13),
= 9.9 Hz); 7.23, 7.27, 7.36 (all m, 5 H, Ph). 13C NMR, δ: 79.6
(—C≡); 85.1 (HC≡); 105.0 (CH=CHS); 127.5 (Cp); 129.2 (Cm),
130.4 (Co); 134.2 (Cipso); 141.1 (=CH—SPh). MS, m/z (Irel (%)):
160 [M]+ (30), 159 [M – H]+ (7), 134 [C8H6S]+ (5), 128
[C10H8]+• (5), 115 [C9H7]+ (21), 109 [PhS]+ (3), 77 [Ph]+ (3),
65 [C5H5]+ (3), 51 [C4H3]+ (5). Found (%): C, 75.15; H, 4.76;
S, 19.84. C10H8S. Calculated (%): C, 74.95; H, 5.03; S, 20.01.
1ꢀPhenylselanylbutꢀ1ꢀenꢀ3ꢀyne (4b) (identified in the mixꢀ
ture with compound 5b). Compound 4b was obtained in the
highest yield (35%) (see Table 1, entry 9) from Ph2Se2 (4.0 g,
0.0128 mol), KOH (3.6 g, 0.064 mol), and dichlorobutyne 1
(3.15 g, 0.0256 mol) in hydrazine hydrate (16 mL). Vacuum
distillation of the residue gave the fraction with b.p. 93—97 °C
(2 Torr) containing compounds 4b and 5b in the ratio of 1 : 0.6. IR,
ν/cm–1: 3285 (H—C≡C), 2091 (C≡C). 1H NMR, δ: 3.40 (d, 1 H,
HC≡, 4JH,H = 2.2 Hz); 5.94 (dd, 1 H, =CH—C≡, 3JH,H = 9.7 Hz,
4JH,H = 2.2 Hz); 7.07 (d, 1 H, =CH—Se, 3JH,H = 9.7 Hz); 7.30,
7.50 (both m, 5 H, SePh). 13C NMR, δ: 80.6 (—C≡); 85.0 (HC≡);
•
•
+
•
84 [C4H4S]+ (22), 83 [C4H3S]+ (17), 58 [C4H10
[CH3S]+ (3).
]
(8), 47
•
•
4ꢀPhenylsulfanylbutꢀ1ꢀenꢀ3ꢀyne (5a) (characterized in the
mixture with 1ꢀphenylsulfanylbutꢀ1ꢀenꢀ3ꢀyne 4a). Product 5a
was obtained in the highest yield (37%) (see Table 1, entry 2) from
diphenyl disulfide (5.46 g, 0.025 mol), KOH (7.0 g, 0.125 mol),
and dichlorobutyne 1 (6.15 g, 0.05 mol) in hydrazine hydrate
(30 mL). IR, ν/cm–1: 2159 (C≡C). 1H NMR, δ: 5.46, 5.64 (both dd,
2
3
cis
3
trans
2 H, CH2=, JH,H = 2.0 Hz, JH,H = 11.3 Hz, JH,H
=
3
cis
= 17.5 Hz); 5.93 (dd, 1 H, =CH—C≡, JH,H = 11.3 Hz,
3JH,Htrans = 17.5 Hz); 7.15, 7.22, 7.37 (all m, 5 H, SPh). 13C NMR,
δ: 76.3 (S—C≡); 97.0 (—C≡C—S); 116.7 (=CH—C≡); 126.2 (Cm);
126.5 (Cp); 126.7 (=CH2); 129.2 (Co); 132.6 (Cipso). MS, m/z
(Irel (%)): 160 [M]+• (12), 159 [M – H]+ (6), 134 [C8H6S]+• (5),
2
108.7 (CH=CHSe, JSe,C = 15.3 Hz); 128.6 (Cipso); 129.1 (Cp),
2
129.4 (Cm); 133.1 (Co, JSe,C = 11.9 Hz); 139.6 (SeCH=,
1JSe,C = 115.4 Hz). 77Se NMR, δ: 417.9. MS, m/z (Irel (%)): 208
128 [C10H8]+ (5), 127 [C10H7]+ (2), 116 [C9H8]+ (6), 115
[C9H7]+ (12), 109 [PhS]+ (4), 77 [C6H5]+ (4), 65 [C5H5]+ (2),
51 [C4H3]+ (9), 50 [C4H2]+• (4).
•
•
+
+
[M]+ (20), 157 [PhSe] (3), 128 [C10H8]+ (41), 115 [C9H7]
•
•
(5), 77 [C6H5]+ (6), 51 [C4H3]+ (6). Found (%): C, 57.58;
H, 3.99; Se, 38.50. C10H8Se. Calculated (%): C, 57.99; H, 3.89;
Se, 38.12.
4ꢀPhenylselanylbutꢀ1ꢀenꢀ3ꢀyne (5b) (characterized in the
mixture with compound 4c). This compound was obtained in the
highest yield of 12% (see Table 1, entry 9, the description of the
experiment see above). IR, ν/cm–1: 2147 (C≡C). 1H NMR, δ:
5.45, 5.64 (both dd, 2 H, CH2=, 2JH,H = 1.9 Hz, 3JH,Hcis = 11.1 Hz,
3JH,Htrans = 17.5 Hz); 5.94 (dd, 1 H, CH=CH2, 3JH,Hcis = 11.1 Hz,
3JH,Htrans = 17.5 Hz); 7.30, 7.50 (both m, 5 H, SePh). 13C NMR,
δ: 70.1 (≡C—Se); 101.9 (—C≡C—Se); 104.4 (=CH—C≡C); 119.2
(Cipso); 127.1 (Cp); 127.9 (Cm); 129.5 (Co ); 129.9 (=CH2). 77Se
1ꢀBenzylsulfanylbutꢀ1ꢀenꢀ3ꢀyne (4c) (identified in the mixꢀ
ture with compounds 3c, 5c, and 6). Compound 4c was obtained
in 25% yield (see Table 1, entry 13) from dibenzyl disulfide
(5.5 g, 0.0223 mol), KOH (6.26 g, 0.112 mol), and dichloroꢀ
butyne 1 (5.49 g, 0.0446 mol). Attempted vacuum distillation of
the resulting mixture led to its intense decomposition. IR,
ν/cm–1: 3284 (H—C≡C), 2090 (C≡C). 1H NMR, δ: 3.35 (d, 1 H,
4
NMR, δ: 372.5 (q, 2JSe,H = 13.3). MS, m/z (Irel (%)): 208 [M]+
•
HC≡, JH,H = 2.3 Hz); 3.91 (s, 2 H, SCH2Ph); 5.40 (dd, 1 H,
3
4
=CH—C≡, JH,H = 9.9 Hz, JH,H = 2.3 Hz); 6.50 (d, 1 H,
=CH—S, 3JH,H = 9.9 Hz); 7.12—7.32 (m, 5 H, Ph). 13C NMR,
δ: 37.4 (SCH2Ph); 79.0 (—C≡); 85.3 (HC≡); 104.0 (CH=CHS);
127.1 (Cp); 128.5 (Cm); 128.9 (Co); 137.5 (Cipso); 140.8 (=CHS).
(22), 128 [C10H8]+• (41), 115 [C9H7]+ (5), 102 [C8H6]+• (6), 77
[C6H5]+ (6), 51 [C4H3]+ (5).
4ꢀBenzylsulfanylbutꢀ1ꢀenꢀ3ꢀyne (5c) (characterized in the
mixture with other products). Compound 5c was obtained in the
highest yield (9%) (see Table 1, entry 13). IR, ν/cm–1: 2156
(C≡C). 1H NMR, δ: 3.89 (s, 2 H, SCH2Ph); 5.33, 5.48 (both dd,
MS, m/z (Irel (%)): 174 [M]+ (11), 173 [M – H]+ (10), 91
•
[C6H5CH2]+ (64), 65 [C5H5]+ (10), 51 [C4H3]+ (5).
3
trans
3
cis
2
1ꢀBenzylselanylbutꢀ1ꢀenꢀ3ꢀyne (4d) (identified in the mixꢀ
ture with other products). The product 4d was obtained in ~8%
yield (see Table 1, entry 16) from dibenzyl diselenide (1.0 g,
0.003 mol), KOH (0.83 g, 0.015 mol), and dichlorobutyne 1
2 H, CH2=, JH,H
= 17.4 Hz, JH,H = 11.1 Hz, JH,H
=
3
trans
= 2.2 Hz); 5.78 (dd, 1 H, =CH—C≡, JH,H
= 17.4 Hz,
3JH,Hcis = 11.1 Hz); 7.12—7.32 (m, 5 H, Ph). 13C NMR, δ: 40.2
(SCH2Ph); 79.9 (≡C—S); 94.2 (—C≡C—S); 116.9 (=CH—C≡);
125.6 (=CH2); the signals for the carbon atoms of the benzene
ring are in the range of 127.0—137.5 ppm, their unambiguous
(0.72 g, 0.006 mol) in hydrazine hydrate (4 mL). IR, ν/cm–1
:
3280 (HC≡), 2090 (C≡C). 1H NMR, δ: 3.32 (d, 1 H, HC≡,
4JH,H = 2.5 Hz); 3.96 (s, 2 H, SeCH2Ph); 5.81 (dd, 1 H, =CH—C≡,
assignment was impossible. MS, m/z (Irel (%)): 174 [M]+ (8),
173 [M – H]+ (14), 141 [M – SH]+, 91 [PhCH2]+ (58), 65
[C5H5]+ (7), 51 [C4H3]+ (4).
•
4
3JH,H = 9.8 Hz, JH,H = 2.5 Hz); 6.85 (d, 1 H, =CH—Se,
3JH,H = 9.8 Hz); the signals for the aromatic protons are in the
range 7.13—7.28 ppm. 13C NMR, δ: 32.8 (CH2Se); 84.8 (HC≡);
108.4 (=CH—C≡); 137.4 ((SeCH=); the signals for the carbon
4ꢀBenzylselanylbutꢀ1ꢀenꢀ3ꢀyne (5d) (characterized in the
mixture with other compounds). Product 5d was obtained in 6%

Chalcogenation of 1,4ꢀdichlorobutꢀ2ꢀyne
Russ.Chem.Bull., Int.Ed., Vol. 64, No. 9, September, 2015 2089
yield (see Table 1, entry 16) by the method described above. IR,
ν/cm–1: 2148 (C≡C). 1H NMR, δ: 5.22, 5.48 (both dd, 2 H,
=CH2, 3JH,Htrans = 17.6 Hz, 3JH,Hcis = 11.3 Hz, 2JH,H = 2.2 Hz);
5.81 (dd, 1 H, =CH—). Unambiguous assignment of other sigꢀ
nals and signals in the 13C NMR spectrum was impossible. MS,
m/z (Irel (%)): 222 [M]+• (14), 141 [M – SeH]+ (8), 91 [PhCH2]+
(63), 65 [C5H5]+ (10), 51 [C4H3]+ (5).
9. Y. Besace, Bull. Soc. Chim. Fr., 1971, 1793.
10. E. N. Deryagina, N. V. Russavskaya, L. K. Papernaya, E. P.
Levanova, E. N. Sukhomazova, N. A. Korchevin, Russ.
Chem. Bull. (Int. Ed.), 2005, 54, 2473 [Izv. Akad. Nauk, Ser.
Khim., 2005, 2395].
11. E. P. Levanova, V. S. Vakhrina, V. A. Grabel´nykh, I. B.
Rozentsveig, N. V. Russavskaya, A. I. Albanov, N. A. Koꢀ
rchevin, Russ. Chem. Bull. (Int. Ed.), 2014, 63, 1722 [Izv.
Akad. Nauk, Ser. Khim., 2014, 1722].
12. O. A. Reutov, A. L. Kurts, K. P. Butin. Organicheskaya
khimiya [Organic chemistry], Part 1, BINOM. Laboratoriya
znanii, Moscow, 2004, 567 pp. (in Russian).
13. A. M. Taber, E. A. Mushina, B. A. Krentsel´, Allenovye ugleꢀ
vodorody: poluchenie, svoistva, primenenie [Allene Hydrocarꢀ
bons: Preparation, Properties, Application], Nauka, Moscow,
1987, 205 pp. (in Russian).
14. A. A. Petrov, S. I. Radchenko, K. S. Mingaleva, I. G. Savꢀ
ich, V. B. Lebedev, Zh. Obshch. Khim., 1964, 34, 1899 [J. Gen.
Chem. USSR (Engl. Transl.), 1964, 34].
15. V. A. Ryazantsev, M. D. Stadnichuk, A. A. Petrov, Zh. Obshch.
Khim., 1980, 50, 694 [J. Gen. Chem. USSR (Engl. Transl.),
1980, 50].
16. E. P. Levanova, V. A. Grabel´nykh, V. S. Vakhrina, N. V.
Russavskaya, A. I. Albanov, I. B. Rozentsveig, N. A. Koꢀ
rchevin, Russ. J. Gen. Chem. (Engl. Transl.), 2014, 84, 439
[Zh. Obshch. Khim., 2014, 84, 380].
17. E. P. Levanova, V. A. Grabel´nykh, K. A. Volkova, N. V.
Russavskaya, L. V. Kluba, A. I. Albanov, N. A. Korchevin,
Chem. Heterocycl. Compd. (Engl. Transl.), 2009, 1009 [Khim.
Geterotsikl. Soedin., 2009, 1245].
18. I. B. Rozentsveig, A. V. Popov, E. V. Kondrashov, G. G.
Levkovskaya, Russ. J. Org. Chem. (Engl. Transl.), 2009, 45,
794 [Zh. Org. Khim., 2009, 45, 806].
19. L. R. W. Clemence, H. Park, M. T. Leffler, L. Bluff, US Pat.
2545876; Chem. Abstr., 1952, 46, 30736.
20. E. P. Levanova, V. S. Vakhrina, V. A. Grabel´nykh, I. B.
Rozentsveig, N. V. Russavskaya, A. I. Albanov, E. R. Sanꢀ
zheeva, N. A. Korchevin, Russ. J. Org. Chem. (Engl. Transl.),
2015, 50, 161 [Zh. Org. Khim., 2015, 51, 175].
4ꢀPropylsulfanylbutꢀ1ꢀenꢀ3ꢀyne (5e) (characterized in the
mixture with other reaction products). This compound was obꢀ
tained in 3% yield (see Table 1, entry 18). IR, ν/cm–1: 2156
(C≡C). 1H NMR, δ: 1.04 (t, CH3, overlapped with signals of
other compounds); 1.81 (m, 2 H, CCH2CH3); 2.75 (t, 2 H,
SCH2CH2CH3); 5.42 (d, 1 H, cisꢀCH2=, 3JH,H = 11.1 Hz); 5.58
3
(d, 1 H, transꢀCH2=, JH,H = 17.3 Hz); 5.80 (dd, 1 H, =CH—,
3JH,H = 11.1 Hz, JH,H
= 17.3 Hz). 13C NMR, δ: 12.8
cis
3
trans
(CH3); 22.6 (MeCH2); 37.1 (SCH2); 89.0, 99.9 (—C≡C—); 104.3
(CH2=); 125.1 (=CH—). MS, m/z (Irel (%)): 126 [M]+ (23),
•
+
111 [M – CH3]+ (2), 97 [C5H5S]+ (7), 85 [C4H5S] (5), 84
[C4H4S]+• (14), 83 [C4H3S]+ (6), 82 [M – S]+• (9), 81 [M – SH]+
+
(5), 58 [C4H10
]
• (7).
3ꢀMethylpyrazole (6) was isolated in the individual state. Its
spectral characteristics are completely identical to those reportꢀ
ed in the work.17
The main results were obtained using the material and
technical base of the Baikal Analytical Community User
Center of the Siberian Branch of the Russian Academy of
Sciences.
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Received March 30, 2015;
in revised form May 22, 2015