Metallaborane reaction chemistry. Part 10. Phenylacetylene incorporation via [4,4-(PMe 2Ph) 2- arachno-4-PtCB 8H 12] in a ‘converse’ metalladicarbaborane synthesis of [7,7-(PMe 2Ph) 2- isonido-7,6,8-PtC 2B 6H 7-6-Ph

Abstract

Reaction between PhC CH and [4,4-(PMe 2Ph) 2- arachno-4-PtB 8H 12] ( 1) gives carbons-apart [7,7-(PMe 2Ph) 2- isonido-7,6,8-PtC 2B 6H 7-6-Ph] ( 2), in a ‘converse’ synthesis of a metallacarbaborane, viz. in a synthesis by addition of carbon centres into a pre-formed metallaborane, rather than by metal-centre addition to a pre-formed carbaborane. The long B(3)–B(4) diagonal distance of 2.541(8) Å in the quadrilateral open face is one of the longest so far observed in a metallanonaborane-type compound, and results principally from a restricted orbital contribution of the {Pt(PMe 2Ph) 2} centre to the {PtC 2B 6} cluster bonding system.