Preparation and characterization of arsine derivatives: X-ray crystal structures of As (SitBuMe2)3, As (SiMe3)2(SiPh3), Et3Ga · As(SiMe3)2(SiPh3), and As(SePh)3

As(Si¹BuMe₂)₃ (1) was prepared by the salt-elimination reaction between (Na/K)₃As and ¹BuMe₂SiCl. Mixing LiAs(SiMe₃)₂ with Ph₃SiCl (1:1) yielded As(SiMe₃)₂(SiPh₃) (2) in a good crystalline yield. Reaction of 2 (1:1) with Et₃Ga gave the expected Lewis acid-base adduct Et₃Ga · As(SiMe₃)₂(SiPh₃) (3). The 1:1 mole ratio reaction of In(SePh)₃ with As(SiMe₃)₃ resulted in a ligand redistribution around the indium and arsenic centers to afford As(SePh)₃ (4) in a low yield. The solid-state structures of 1–4 have been established by single-crystal X-ray analysis. Crystal data for 1, monoclinic space group P 2₁/c, with a = 11.112(2), b = 17.453(2), c = 14.199(2) Å, β = 114.89° for Z = 4; 2, orthorhombic space group P c2₁n, with a = 9.236(1), b = 16.612(2), c = 16.803(4) Å for Z = 4; 3, monoclinic space group P 2₁/c, with a = 16.799(1), b = 11.199(2), c = 19.413(3) Å, β = 112.22(1) for Z = 4; 4, trigonal space group R &3macr;, with a = 12.863(5), c = 18.96(1) Å for Z = 6. © 1996 John Wiley & Sons, Inc.