Steric Effects in Heteroboranes. V. 1-Ph-2-Me3Si-1,2-closo-C2B10H10

Article abstract of DOI:10.1107/S010827019400908X

The structure of 1-phenyl-2-trimethylsilyl-1,2-dicarba-closo-dodecarborane(12), C11H24B10Si, has been determined crystallographically.The C_cage-C_cage distance is 1.708 (4) Angstroem, only slightly longer than in the 2-methyl analogue.However, in contrast to the 2-methyl and 2-bromo analogues, relief from steric congestion is afforded by a mutual 'bend back' of both the phenyl and trimethylsilyl groups, the latter involving deformation of valency angles both at Si and the C_cage atom to which it is attached.