Syntheses and Crystal Structures of Two Tin(IV) Complexes with Aminosilane Bearing Ligand

Aminosilane bearing bulky substituents on nitrogen: LH2 (L = Me2Si(NDipp)(2), Dipp = 2,6-diisopropylphenyl) was reacted with BuLi in toluene. The resulting bulky chelating dianion Me2Si(NDipp)(2) was used to synthesize the unusual spirocyclic heterotriatomic complex [Me2Si(NDiPP)(2)](2)Sn (1) by its reaction with SnCl4 and the bulky heterotriatomic complex Me2Si(NDipp)(2)SnPh2 (2) with Ph2SnCl2. 1 belongs to the monoclinic system, space group P2(1)/n with a = 13.193(2), b = 20.663(3), c = 20.403(3) angstrom, beta = 99.954(2)degrees, V = 5478.3(15) angstrom(3), C55H85.5N4Si2Sn, M-r = 977.64, Z = 4, D-c = 1.185 Mg/m(3), mu(MoK alpha) = 0.547 mm(-1), F(000) = 2086, S = 1.000, the final R = 0.0614 and wR = 0.1322 for 14446 observed reflections (I> 2 sigma(I)) and R = 0.0797 and wR = 0.1456 for all data. 2 belongs to the triclinic system, space group P (1) over bar with a = 10.36(15), b = 13.204(7), c = 14.363(7) angstrom, alpha = 90.214(10), beta = 106.182(7), gamma = 109.854(8)degrees, V= 1764.4(15) angstrom(3), C38H50N2SiSn, M-r = 681.58, Z = 2, D-c = 1.283 Mg/m(3), mu(MoK alpha) = 0.785 mm(-1), F(000) = 712, S = 1.002, the final R = 0.0498 and wR = 0.0955 for 7533 observed reflections (I > 2 sigma(I)) and R = 0.0676 and wR = 0.1018 for all data. In the structure of 1, the tin atom is located in the spirocyclic center of the two fused four-membered SnN2Si rings. The two complexes were characterized by H-1 NMR, elemental analysis, and single-crystal X-ray structural analysis.