The crystal and molecular structure of tetrahydro-thiazole-2-thione

The crystal of tetrahydrothiazole-2-thione (TTT) belongs to monoclinic system. Space group P2₁/n. There are eight molecules in an unit cell with parameters a = 13.844(7)Å, b = 5.614 (2)Å, c = 13.516 (7)Å, β=95.08 (5)°, V =1046.3 (9)ų The three dimensional intensity data were obtained on a Syntex R3 four-circle diffractometer, and the number of the independent diffractions amounted to 1906. The structure was solved by direct method and refined by block-diagonal least-squares method. The final R is 0.082. In crystal, the molecular structure is between 1 and 2 in which S(1), S(2), N and C(1) are coplanar with conjugation. We use CNDO/2 programmes written by ourselves on Eclipse computer to compute the electronic energies, molecular total energies, dipole moments, the charge densities and net charges of each atom of TTT and its N-benzoylated derivative. The color of the acylated TTT and its properties for aminolysis are discussed.