Lewis acid-promoted vinyl rearrangement and halogen exchange of platinum-fluoro-olefin complexes

Abstract

Treatment of the complexes Pt[CF₂:CF(CF₃)]L₂[L = PPh₃, PPh₂Me, (Ph₂PCH₂)₂, or AsPh₃] with stannic chloride yields products dependent on the nature of L. With PPh₂Me or AsPh₃, perfluoropropene is displaced, but with PPh₃ or diphos the vinylplatinum compounds trans-PtCl[CCl:CF(CF₃)](PPh₃)₂ and PtCl[CF:CF(CF3)](diphos) are formed, respectively. Reaction of SnCl₄ with Pt(C₂F₄)L₂(L = PPh₃, PPh₂Me, or AsPh₃) or with Pt[trans(CF₃)CF:CF(CF₃)](AsPh₃)₂ leads to displacement of the fluoro-olefin and formation of PtCl₂L₂. In contrast, the tin halide reacts with Pt[trans(CF₃)CF:CF(CF₃)]L₂[L = PPh₃, PPh₂Me, or (Ph₂PCH₂)₂] to yield vinylplatinum compounds cis-PtCl[transC(CF₃):CF(CF₃)]L₂. A mechanism for the C–F bond cleavage and stereospecific nature of the reactions is proposed.