Reactions of low-valent metal complexes with fluorocarbons. Part 32. Tris-µ-(t-butyl isocyanide)-tris(t-butyl isocyanide)-triangulo-triplatinum

Abstract

Reaction of [Pt₃(Bu^tNC)₆](1) with hexafluoroacetone affords the five-membered ring metallacycle [{[graphic omitted](CF₃)₂}(Bu_tNC)₂], but with tetrafluoroethylene an octafluorodiplatinacyclohexane complex [(Bu_tNC)₂[graphic omitted]F₂] is formed, which undergoes dynamic behaviour in solution. Treatment of (1) with hexafluoropropene, octafluorobut-2-ene, and 1,1-dicyano-2,2-bis(trifluoromethyl) ethylene yields the three-membered ring complexes [{[graphic omitted]F(CF₃)}(Bu^tNC)₂], [{[graphic omitted]F(CF₃)}(Bu^tNC)₂], and [{[graphic omitted](CN)₂}(Bu^tNC)₂], respectively. Whereas bromotrifluoroethylene and (1) form trans-[PtBr(CF:CF₂)(Bu^tNC)₂], chlorotrifluoroethylene affords [([graphic omitted]FCl)(Bu^tNC)₂] which in solution rearranges to cis-[PtCl(CF:CF₂)(Bu^tNC)₂] and subsequently to trans-[PtCl(CF:CF₂)(Bu^tNC)₂]. Fluorine-19 n.m.r. and i.r. studies reveal that cis-[PtCl(CF:CF₂)(Bu^tNC)₂] reverts to the η²-chlorotrifluoroethylene complex [([graphic omitted]FCl)(Bu^tNC)₂] on recrystailisation of the former from solutions.