MULTIPLE BONDS BETWEEN SN AND S - SYNTHESIS AND STRUCTURAL CHARACTERIZATION OF (CYNC((T)BU)NCY)(2)SN=S AND [(CYNC(ME)NCY)(2)SN(MU-S)](2)

Two new sulfide complexes of tin have been prepared by the reaction of styrene sulfide with novel tin(II) amidinate complexes. These compoun ds exhibit two very different bonding modes for the sulfide ligand; in one case, S=Sn(CyNC((t)Bu)NCy)(2) (3), a terminal Sn=S moiety was fou nd while in the other case, [(CyNC(Me)NCy)(2)Sn-(mu-S)](2) (4), a brid ging sulfide dimer is observed. The starting complexes were prepared b y the reaction of 2 equiv of the appropriate lithium amidinate with Sn Cl2 to yield the new species Sn(CyNC(R)NCy)(2) [Cy = cyclohexyl; R = M e (1); R = (t)Bu (2)]. This account represents the first report of (Cy NC((t)Bu)NCy)(-) and the coordination chemistry of this bulky ligand. Spectroscopic and elemental analyses confirmed the formulas of all of these new species. Compounds 2, 3, and 4 were further characterized by X-ray crystallography. Compound 2 possesses a coordination geometry b ased on a trigonal bipyramid with one equatorial vertex occupied by th e stereochemically active lone pair of electrons. Crystal data for 2: monoclinic, P21/c, a = 18.944(5) Angstrom, b = 10.604(2) Angstrom, c = 19.423(2) Angstrom, beta = = 95.99(1)degrees, Z = 4, R = 0.046, R(w) = 0.049. Crystal data for 3: orthorhombic, Cmcm, a = 12.3788(23) Angst rom, b = 14.1977(15) Angstrom, c = 20.670(3) Angstrom, Z = 4, R = 0.05 7, R(w) = 0.070. Crystal data for 4: monoclinic, P2/n, a = 13.0395(2) Angstrom, b = 13.0263(2) Angstrom, c = 23.8856(2) Angstrom, beta = 95. 719(3)degrees, R = 0.055, R(w) 0.044.