Stability and reactivity of the cis-Pt^IIR(alkyne) fragment (R = alkyl): an unprecedented rearrangement to form the Pt^II(η³-allyl) moiety

Abstract

The complexes [PtR(η²-E-MeO₂CCH= CHCO₂Me)(phen)]⁺BF₄^- (R = Me 1a or Et 1b; phen = 1,10-phenanthroline) reacted with alkynes yielding the corresponding products [PtR(η²-alkyne)(phen)]⁺BF₄ ^-2. These can be isolated in the case of disubstituted electron-rich alkynes, while the electron-poor MeO₂CC≡CCO₂Me inserted into the Pt–R bond leading to the corresponding σ-vinyl derivative. Type 2 complexes containing alk-1-ynes undergo an unprecedented rearrangement to form stable [Pt(η³-allyl)(phen)]⁺BF₄ ^- products. Mechanistic aspects of the reaction are discussed.

References

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