Further Investigations into the Synthesis and Characterization of Halo-Boron-Arsenic Compounds: X-Ray Crystal Structures of X3B · As(SiMe3)3(X = Cl, I) and [I2BAs(SiMe3)2]2

Abstract

A low-temperature (−78 C) 1:1 mole ratio reaction of Bl3 with As(SiMe3)3 produced the 1:1 Lewis acid-base adduct l3B.As(SiMe3)3 (1), whereas the identical reaction performed at room temperature (previously reported)1 produced the dimeric compound, [l2BAs(SiMe3)2]2 (2). Full characterization of compound 1 was conducted, including a single-crystal X-ray structural determination. The previously unreported X-ray crystal structures of 2 and Cl3 B·As(SiMe3)3 (3) have also been elucidated. Crystals of 1 belong to the orthorhombic space group Pbca, with a = 13.8673(13), b = 17.5885(8), c = 22.8784(22) A, V = 5580.1(8) A3, Dcalc = 1.853g cm−3 for Z = 8, and the B-As bond length is 2.104(15) A. Crystals of 2 belong to the monoclinic space group P21/n, with a = 9.836(5), b = 13.682(3), c = 11.701(6) A, V = 1545.8 (12) A3, Dcalc = 2.088 g cm−3 for Z = 4, and the average B-As bond length is 2.13 A. Compound 3 crystallizes in the orthorhombic space group Pbca, with a = 13.4109(2), b = 17.1371 (2), c = 21.7996(3) A, V =...