SYNTHESIS AND CHARACTERIZATION OF INDIUM ARSENIC COMPOUNDS CONTAINING A 4-MEMBERED IN-AS-IN-AS OR IN-AS-IN-CL RING - CRYSTAL-STRUCTURES OF [(ME3SICH2)2INAS(SIME3)2]2 AND (ME3SICH2)2INAS(SIME3)2IN(CH2SIME3)2CL

The first four-membered ring compounds with bridging of the indium atoms by two arsenic atoms and with mixed bridging of the indium centers by one arsenic and one chlorine, [(Me3SiCH2)2InAs(SiMe3)2]2 (1) and (Me3SiCH2)2 activated InAs(SiMe3)2In(CH2SiMe3)2Cl (2), to be characterized completely were prepared by the reaction of (Me3SiCH2)2InCl and (Me3Si)3As in 1:1 and 2:1 mol ratios, respectively. X-ray crystallographic analyses showed both the activated In-As-In-As ring of 1 and the activated In-As-In-Cl ring of 2 to be planar. Compound 1 belongs to the orthorhombic system, space group Pbcn (D14(2h)), with four molecules in a unit cell of dimensions a = 12.920 (1) angstrom, b = 21.618 (2) angstrom, and c = 18.797 (2) angstrom. Compound 2 crystallizes in the monoclinic system, space group C2/c (C6(2h)), with four molecules in a unit cell of dimensions a = 19.233 (3) angstrom, b = 10.798 (2) angstrom, c = 20.819 (3) angstrom, and beta = 105.91 (1)-degrees. Compound 1 reacts with 2 equiv of (Me3SiCH2)2InCl to yield 2 as a major product, as evidenced by H-1 and C-13{H-1} NMR and melting point data.