The Syntheses and Characterization of the Bulky Terphenyl Silanes and Chlorosilanes 2,6-Mes₂C₆H₃SiCl₃, 2,6-Trip₂C₆H₃SiCl₃, 2,6-Mes₂C₆H₃SiHCl₂, 2,6-Trip₂C₆H₃SiHCl₂, 2,6-Mes₂C₆H₃SiH₃, 2,6-Trip₂C₆H₃SiH₃ and 2,6-Mes₂C₆H₃SiCl₂SiCl₃

Abstract

The synthesis and characterization of the primary terphenyl silanes and chlorosilanes 2,6-Mes₂C₆H₃SiCl₃ (1a), 2,6-Trip₂C₆H₃SiCl₃ (1b), 2,6-Mes₂C₆H₃SiHCl₂ (2a), 2,6-Trip₂C₆H₃SiHCl₂(2b) 2,6-Mes₂C₆H₃SiH₃(3a), 2,6-Trip₂C₆H₃SiH₃ (3b) and 2,6-Mes₂C₆H₃SiCl₂SiCl₃(4), (where Mes = 2,4,6-Me₃C₆H₂ and Trip = 2,4,6-i-Pr₃C₆H₂) are described. Compounds (1a, 1b), (2a, 2b) and (4) were prepared by the reaction between SiCl₄, SiHCl₃ or Si₂Cl₆, respectively, and the appropriate aryl lithium reagent (2,6-Mes₂C₆H₃Li or 2,6-Trip₂C₆H₃Li·OEt₂). Compounds (3a) and (3b) were prepared by reduction of (1a) and (1b) with LiAlH₄, respectively. The derivatives (1a) - (3a) were characterized by ¹H, ¹³C, 29Si NMR and IR spectroscopy. The structures of (1a), (1b) and (4) have been determined. Crystal data with CuKα (λ = 1.54178 A) at 130 K: (1a), a = 9.074(2) A, b = 16.681(3) A, c = 15.842(3) Å, β = 105.20(3)°, V = 2313.9(8) A³, Z = 4, space group P2¹/c, 2772 (I > 2σ(I)) data, R = 0.042; (1b), a = 12.197(2) A, b = 25.602(5) A, c = 11.098(2) Å, V = 3465.5(11) ų, Z = 4, space group Pnma, 2131 (I >2 σ(I)) data, R = 0.061; (4), a = 10.799(2) Å, b = 15.355(3) Å, c = 16.724(3) Å, β = 106.907(13)°, V = 2653.2(8) ų, Z = 4, space group P2₁/n, 2852 (I > 2 σ(I)) data, R = 0.047.