anti-2,2,3,3,6,6,7,7,10,10,11,11,14,14,15,15-Hexadeca-methyl-2,3,6,7,10,11,14,15-octa-silapenta-cyclo-[10.4.2.2(4,9).0(5,8).0(13,16)]icosa-1(17),4,8,12(18),13(16),19-hexa-ene

Acta Crystallogr Sect E Struct Rep Online. 2013 Mar 1;69(Pt 3):o341. doi: 10.1107/S1600536813002584. Epub 2013 Feb 6.

Abstract

The title compound, C28H52Si8, was synthesized by condensation of two mol-ecules of 1,2,3,4-tetra-kis-(chloro-dimethyl-sil-yl)benzene with lithium. The 3,4-disila-1,2-benzocyclo-butene rings in the centrosymmetric molecule are bridged by 1,1,2,2-tetra-methyl-disilanylene chains with an anti conformation. The benzene rings are deformed by fusion with a 3,4-disilacyclo-butene ring resulting in a slight boat conformation. Two Si-C bonds are bent to reduce the steric repulsion between the methyl groups on the two Si atoms and the methyl groups on another two Si atoms.