Further Investigations into the Synthesis and Characterization of Halo-Boron-Arsenic Compounds: X-Ray Crystal Structures of X3·As(SiMe3)3 (X = Cl, I) and [I2BAs(SiMe3)2]2
Affiliations: Department of Chemistry, Paul M. Gross Chemical Laboratory, Duke University, Durham, North Carolina 27708-0346; | Department of Chemistry, Venable Hall, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27514; | Department of Chemistry, Kolthoff Hall, University of Minnesota, Minneapolis, MN 55455
Note: [] Author for correspondence.
Abstract: A low-temperature (−78°C) 1:1 mole ratio reaction of BI3 with As(SiMe3)3, produced the 1:1 Lewis acid-base adduct I3B·As(SiMe3)3 (l), whereas the identical reaction performed at room temperature (previously reported)1 produced the dimeric compound, [I2BAs(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) Å, V = 5580.1(8) Å3, Dcalc = 1.853 g cm−3 for Z = 8, and the B-As bond length is 2.104(15)Å. Crystals of 2 belong to the monoclinic space group P21/n , with a = 9.836(5), b = 13.682(3), c = 11.701(6) Å, V = 1545.8 (12) Å3,D calc= 2.088 g cm−3 for Z = 4, and the average B-As bond length is 2.13 Å. Compound 3 crystallizes in the orthorhombic space group Pbca, with a = 13.4109(2), b = 17.1371(2), c = 21.7996(3) Å, V=5010.07(12) Å3, Dcalc= 1.336 g cm−3 for Z = 8, and the B-As bond length is 2.118(6) Å.
