Synthesis and crystal structure of 2-morpholinylthioformyl-2-phenyl-4-morpholinyl-5-phenyl-1, 3-dithiole

The title compound 2-morpholinylthioformyl-2-phenyl-4-morpholinyl-5-phenyl- 1,3-dithiole (C24H26N2O2S3 M-r = 470.66) was obtained by the reaction of al pha -thiobenzoylthioformmorpholine (1) with trimethylphosphite. The crystal is monoclinic, space group P2(1)/n, with unit cell parameters: a = 9.746(2 ), b = 21.124 (8), c = 11.484(3) Angstrom, beta = 99.98(2)degrees, Z = 4, V = 2328(1) Angstrom (3), D-c = 1.343 g/cm(3), mu (MoK alpha) = 3.42 cm(-1), F(000) = 992.00. R = 0.054, R-w = 0.062 for 2426 observed reflections (I>2 .00 sigma (I)). X-ray analysis reveals that interatomic distance for C(1) - C(2) is 1.338(5) Angstrom, indicating that it is a double bond. The atoms C(1), C(2), C(3), S(1) and S(2) form al, 3-dithiole ring, in which S(1), C( 1), C(2) and S(2) are coplanar. The X-ray results support our proposed mech anism for the reaction.