Metallaborane chemistry. Part 9. Oxidative–insertion reactions of zerovalent nickel and platinum complexes with 1,7-dicarba-closo-octaborane, 4,5-dicarba-closo-nonaborane, 1,6-dicarba-closo-decaborane, and their C- methyl derivatives
Abstract
The complexes [Pt(PEt3)3], [Pt(trans-stilbene)(PR′3)2](R′= Et or Me), [M(cod)(PMe3)2](M = Pt or Ni; cod = cyclo-octa-1,5-diene), and [Ni(cod)(PEt3)2] react with closo-1,7-R2-1,7-C2B6H6(R = H or Me), closo-4,5-R2-4,5-C2B7H7, and closo-1,6-C2B8H10 to give the carbametallaboranes closo-[4,5-R2-6,6-(PR′3)-4,5,6-C2MB6H6](M = Pt, R = H, R′= Me; M = Pt, R = Me, R′= Me or Et; M = Ni, R = Me, R′= Me or Et), nido-[4,5-R2-7,7-(PR′3)-4,5,7-C2PtB6H6](R = H, R′= Me, and R = Me, R′= Et), nido-[2,8-R2-10,10-(PR′3)-2,8,10-C2MB7H7](M = Pt, R′= Et, R = H or Me; M = Ni, R = H, R′= Et, and R = Me, R′= Me), and nido-[µ-(6,10)-{ Pt(PMe3)2}-10,10-(PMe3)2-7,9,10-C2PtB8H10], respectively. The latter compound, on reaction with activated charcoal, afforded the compound nido-[10,10-(PMe3)2-7,9,10-C2PtB8H10]. The 1H, 11B, and 31P n.m.r. spectra of the new compounds are reported, and their mechanism of formation and molecular structures discussed.