SYNTHESIS OF 1,3-BIS(ORGANYLCHALCOGENO)PROPANES
95
Reaction of 1-bromo-3-chloropropane (III) with
an equimolar mixture of potassium disulfide and
potassium ditelluride. A solution of potassium di-
sulfide was prepared as described above from 5.6 g
KOH, 40 g of hydrazine hydrate, and 3.2 g of sulfur
powder. Under analogous conditions, a solution of
potassium ditelluride was prepared from 12.8 g of
tellurium powder in another flask. The solutions were
combined, and 15.74 g of 1-bromo-3-chloropropane
(III) was added at 42 C. The mixture was stirred for
3 h at 65 C, and the precipitate of oligomer IVb,
16.2 g, was separated, washed with water, and dried.
The product was a black viscous sticky material, mp
extract a cyclic compound, 1,2-dichalcogenolane Ia If;
their structure was confirmed by the GC MS data.
The yields are given in Table 2, and the mass spectra
of Id If are presented in Table 3.
1-Methylselanyl-3-methylsulfanylpropane (IIg).
a. A flask was charged with 3 g of oligomer IVa,
3.3 g of potassium hydroxide, and 15 g of hydrazine
hydrate, and the mixture was stirred for 2 h at 80
85 C. The mixture was then cooled to 27 C, 5.7 g of
methyl iodide was slowly added over a period of 2 h,
and the mixture was stirred for 2.5 h at 35 40 C,
cooled to room temperature, and extracted with di-
ethyl ether. The extract was washed with water to pH
7 and dried over CaCl2, and the solvent was distilled
off. According to the GLC and GC MS data, the re-
sidue, 2.3 g, was a mixture of 1,3-bis(methylsulfanyl)-
propane (IIa), 1,3-bis(methylselanyl)propane (IIc),
and 1-methylselanyl-3-methylsulfanylpropane (IIg).
1
80 120 C (decomp.). IR spectrum, , cm : 2962,
2948, 1461, 1434, 1424, 1410, 1402, 1330, 1272,
1239, 1198, 1169, 1119, 1072, 1035, 942, 905, 895,
868, 787, 752, 689, 474. In another experiment with a
sulfur-to-tellurium ratio of 1:2 we used 1.6 g of sulfur,
12.8 g of tellurium, and 11.94 g of dihalopropane III.
The product, oligomer IVc (15 g), was a black
viscous sticky material, mp 75 95 C. IR spectrum, ,
1
The yields are given in Table 4. H NMR spectrum of
IIg, , ppm: 1.93 m (CCH2C), 2.08 s (CH3S), 2.58 m
(CH3Se, CH2S, CH2Se).
1
cm : 2960, 2917, 2850, 1708, 1652, 1433, 1413,
1400, 1330, 1296, 1272, 1246, 1233, 1193, 1169,
1119, 1085, 1072, 1036, 943, 906, 895, 869, 787, 757,
693, 478.
b. Dimethyl disulfide, 1 g, was added to a solution
of 2.8 g of KOH in 12.5 g of hydrazine hydrate, and
the mixture was stirred for 2 h at 80 85 C. Under
analogous conditions, reductive cleavage of 2 g of
dimethyl diselenide was performed in another flask.
The resulting solutions were combined, and 9.55 g of
1-bromo-3-chloropropane (III) was slowly added at
25 C. The mixture was stirred for 2.5 h at 75 C,
cooled to room temperature, and extracted with me-
thylene chloride. The extract was washed with water
to pH 7 and dried over CaCl2, and the solvent was
distilled off. According to the GLC and GC MS data,
the residue, 2.5 g, was a mixture of 1,3-bis(methyl-
sulfanyl)propane (IIa), 1,3-bis(methylselanyl)propane
(IIc), and 1-methylselanyl-3- methylsulfanylpropane
(IIg) ([M]+ 184). The yields are given in the text.
Reaction of 1-bromo-3-chloropropane (III) with
an equimolar mixture of potassium diselenide and
potassium ditelluride. A solution of K2Se2 was
prepared as described above from 2.8 g KOH, 20 g of
hydrazine hydrate, and 3.95 g of selenium. Under
analogous conditions, a solution of K2Te2 was pre-
pared from 6.4 g of tellurium powder in another flask.
The solutions were combined, and 11.8 g of 1-bromo-
3-chloropropane (III) was added at 50 55 C. The
mixture was stirred for 1.5 h at 80 85 C, and the
precipitate of oligomer IVd, 11.5 g, was separated,
washed with water, and dried. The product was a dark
brown viscous sticky material, mp 45 180 C
1
1-Ethylselanyl-3-ethylsulfanylpropane (IIh).
Following the procedure described above for com-
pound IIg, alkylation of the reductive cleavage pro-
ducts of oligomer IVa with 8.6 g of ethyl bromide
gave a mixture of 1,3-bis(ethylsulfanyl)propane (IIb),
1,3-bis(ethylselanyl)propane (IId), and 1-ethylselanyl-
3-ethylsulfanylpropane (IIh) (GLC and GC MS data).
The yields are given in Table 4.
(decomp.). IR spectrum, , cm : 3320, 3267, 2956,
2917, 2847, 1477, 1460, 1434, 1421, 1407, 1334,
1313, 1279, 1209, 1189, 1173, 1135, 1097, 1040, 954,
934, 904, 878, 840, 807, 755, 722, 702, 538, 488, 412.
In another experiment with a selenium-to-tellurium
ratio of 1:2 we used 3.95 g of selenium, 12.8 g of
tellurium, and 17.7 g of dihalopropane III. The reac-
tion was carried out as described above. The product,
oligomer IVe, 20 g, was a black viscous sticky ma-
By vacuum distillation of the residue we isolated a
fraction with bp 91 95 C (1.5 mm), which contained
compounds IId and IIh at a ratio of 1:1 (GLC).
1
terial, mp 67 180 C (decomp.). IR spectrum, , cm :
2970, 2921, 1434, 1410, 1332, 1313, 1277, 1210,
1170, 1124, 1084, 1039, 954, 929, 897, 877, 807,
792, 754, 718, 698, 649, 587, 559, 530, 486.
1
Compound IId. H NMR spectrum, , ppm: 1.39 t
3
(CH3CH2Se, JHH = 5.8 Hz), 1.99 quint (CCH2C,
3
3JHH = 5.8 Hz), 2.55 q (CH3CH2Se, JHH = 5.8 Hz),
3
1,2-Dichalcogenolanes Ia If (general procedure).
Oligomer IVa IVe was treated with chloroform to
2.65 t (CH2CH2Se, JHH = 5.8 Hz). 13C NMR spec-
trum, C, ppm: 15.74 (CH3CH2Se), 17.18 (SeCH2
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 77 No. 1 2007