Metallaborane reaction chemistry. Part 10. Phenylacetylene incorporation via [4,4-(PMe2Ph)2-arachno-4-PtCB8H12] in a 'converse' metalladicarbaborane synthesis of [7,7-(PMe2Ph)2-isonido-7,6,8-PtC2B6H7-6-Ph]

PhCCH and [(PMe2Ph)2PtB8H12] (1) give carbons-apart [7,7-(PMe2Ph)2-isonido-7,6,8-PtC2B6H7-6-Ph] (2) in a 'converse' metallacarbaborane synthesis. The B(3)-B(4) diagonal distance 2.541(8) Å in the stretched quadrilateral isonido open face of 2 is one of the longest so far observed in a metallanonaborane-type compound, and results from orbital control of the {PtC2B6} cluster bonding system by the {Pt(PMe2Ph)2} centre.