Cycloaddition of di(2ꢀpyridyl) diselenide
Russ.Chem.Bull., Int.Ed., Vol. 60, No. 10, October, 2011
2061
as a solvent was purified by distillation over P2O5. Styrene (1)
was used freshly distilled. Di(2ꢀpyridyl) diselenide (2) (m.p.
48—49 °C) and 2ꢀpyridineselenenyl chloride (4) (m.p. 118—119 °C)
were synthesized according to the known procedures.24
Table 3. Principal crystallographic data and parameters of reꢀ
finement for compounds 3a and 3b
Compound
3a
3b
Reaction of styrene 1 with the antimony pentachloride—diꢀ
(2ꢀpyridyl) diselenide 2 system (general procedure). A solution of
SbCl5 (0.075 g, 0.25 mmol) in anhydrous CH2Cl2 (10 mL) was
added to a solution of diselenide 2 (0.079 g, 0.25 mmol) in
CH2Cl2 (10 mL) at –40 °C with stirring under dry argon. Forꢀ
mation of white amorphous precipitate was observed. The reacꢀ
tion mixture was stirred for 15 min at –40 °C, followed by
a dropwise addition of a solution of styrene 1 (0.052 g, 0.5 mmol)
in CH2Cl2 (5 mL), then the mixture was stirred at this temperaꢀ
ture for 30 min until the precipitate was completely dissolved.
The mixture was warmed to room temperature, the solvent was
evaporated in vacuo. After recrystallization of the residue from
CH2Cl2, compound 3a (0.20 g, 97%) was obtained.
Molecular formula
Molecular weight
T/K
Crystal system
Space group
a/Å
b/Å
c/Å
α/deg
β/deg
C26H24N2Se2SbCl5 C13H12NSeSbCl6
821.40
100
595.65
100
Monoclinic
P21/n
6.7822(3)
12.1732(6)
17.1401(8)
90
P21/c
13.5164(4)
10.9651(3)
13.5804(4)
90
92.143(1)
90
111.453(1)
90
γ/deg
V/Å3
1414.12(11)
4
1873.29(9)
Z2
Reactions with the ratio alkene : diselenide : antimony penꢀ
tachloride equal to 2 : 1 : 2 was performed similarly. After heatꢀ
ing the reaction mixture to room temperatures, the solvent was
half evaporated in vacuo, the thus formed crystals of compound
3b were filtered off. The mother liquor was concentrated, the
residue was recrystallized from CH2Cl2 to obtain compound 3a.
Bis(3ꢀphenylꢀ2,3ꢀdihydro[1,3]selenazolo[3,2ꢀa]pyridiniumꢀ
4) pentchloroantimonate(III) (3a). Light yellow crystals, m.p.
238—240 °C. Found (%): C, 37.89; H, 2.87. C26H24Cl5N2SbSe2.
dcalc/g cm–3
F(000)
1.929
796
4.043
60
2.112
1136
4.265
65
μ/mm–
1
2θmax/deg
Number of measured
reflections
Number of independent
reflections
17498
27401
4100
6833
1
Rint
0.034
3445
0.029
6198
Calculated (%): C, 38.02; H, 2.94. H NMR, δ: 3.81 (dd, 1 H,
Number of reflections
with I > 2σ(I)
Number of refined
parameters
R1 (I > 2σ(I))
wR2 (all the data)
GOF
H(2), J = 10.3 Hz, J = 7.3 Hz); 4.29 (dd, 1 H, H(2), J = 10.3 Hz,
J = 7.3 Hz); 6.61 (t, 1 H, H(3), J = 7.3 Hz); 7.40 (m, 2 H, Ph);
7.48 (m, 3 H, Ph); 7.74 (dd, 1 H, H(6), J = 7.3 Hz, J = 5.9 Hz);
8.32 (dd, 1 H, H(7), J = 8.8 Hz, J = 7.3 Hz); 8.42 (d, 1 H, H(8),
J = 8.8 Hz); 8.51 (d, 1 H, H(5), J = 5.9 Hz).
3ꢀPhenylꢀ2,3ꢀdihydro[1,3]selenazolo[3,2ꢀa]pyridiniumꢀ4
hexachloroantimonate(V) (3b). Yellow crystals, m.p. 188—190 °C.
Found (%): C, 26.12; H, 1.97. C13H12Cl6NSbSe. Calculated (%):
C, 26.21; H, 2.03. The 1H NMR spectrum of the salts 3b is
identical to the spectrum of compound 3a.
169
199
0.0263
0.0594
0.0215
0.0537
1.001
1.007
Transmission,
Tmin/Tmax
0.582/0.643
0.415/0.567
Reaction of styrene 1 with 2ꢀpyridineselenenyl chloride 4 in
the presence of antimony chlorides (general procedure). A soluꢀ
tion of SbCl3 (0.057 g, 0.25 mmol) in anhydrous CH2Cl2 (10 mL)
was added to a suspension of finely powdered 2ꢀpyridineseleneꢀ
nyl chloride (4) (0.096 g, 0.5 mmol) in CH2Cl2 (15 mL) at –40 °C
with stirring under dry argon. Formation of white amorphous
precipitate was observed. The reaction mixture was stirred for
15 min at –40 °C, followed by a dropwise addition of a solution
of styrene 1 (0.052 g, 0.5 mmol) in CH2Cl2 (5 mL), then the
mixture was stirred at this temperature for 30 min until the preꢀ
cipitate was completely dissolved. The mixture was warmed to
room temperatures, the solvent was evaporated in vacuo. Reꢀ
crystallization of the residue from CH2Cl2 yielded compound 3a
(0.189 g, 92%).
The structures of compounds 3a,b were solved by the direct
method and refined by the fullꢀmatrix least squares method in
the anisotropic approximation for nonhydrogen atoms. The antiꢀ
mony atom in the structure of 3a occupies a particular position
2–
in the center of inversion, resulting in the SbCl5 anion being
disordered over two positions with the equal populations. All the
hydrogen atoms, whose positions were calculated geometrically,
were included into the refinement in the isotropic approximaꢀ
tion with the fixed positional (the riding model) and thermal
(Uiso(H) = 1.2Ueq(C)) parameters. All the calculations were perꢀ
formed using the SHELXTL program package.26
References
The reaction of selenenyl chloride 4 with styrene in the presꢀ
ence of SbCl5 was performed similarly.
Xꢀray diffraction studies of compounds 3a and 3b. Parameters
of the unit cells and intensities of reflections for compounds 3a
and 3b were measured on a Bruker APEXꢀII CCD automatic
threeꢀcircle diffractometer with a twoꢀcoordinate detector
(T = 100 K, MoꢀKα radiation, graphite monochromator, ϕꢀ and
ωꢀscanning). Allowance for the absorption of Xꢀray radiation
was made for the data obtained using the SADABS program.25
The principal crystallographic data are given in Table 3.
1. M. Tiecco, L. Testaferri, M. Tingoli, D. Chianelli, D. Barꢀ
toli, Tetrahedron Lett., 1989, 30, 1417.
2. M. Tiecco, L. Testaferri, M. Tingoli, D. Chianelli, D. Barꢀ
toli, Tetrahedron, 1989, 45, 6819.
3. M. Tiecco, M. Tingoli, L. Testaferri, Pure Appl. Chem., 1993,
65, 715.
4. M. Tiecco, L. Testaferri, M. Tingoli, C. Santi, Tetrahedron
Lett., 1995, 36, 163.
Borisov
