Alkyne Metathesis Reactions of Rhenium(V) Carbyne Complexes

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• 作者：Wei Bai ; Ka-Ho Lee ; Herman H. Y. Sung ; Ian D. Williams ; Zhenyang Lin ; Guochen Jia
• 刊名：Organometallics
• 出版年：2016
• 出版时间：November 28, 2016
• 年：2016
• 卷：35
• 期：22
• 页码：3808-3815
• 全文大小：535K
• ISSN：1520-6041

文摘

Although alkyne metathesis reactions mediated by high-valent d⁰ carbyne complexes are well established, similar reactions mediated by well-defined low-valent (non-d⁰) carbyne complexes are rare. This work demonstrates that d² Re(V) carbyne complexes Re(≡CR)Cl₂(PMe₂Ph)₃ (R = CH₂(o-C₆H₄Br), Ph, CO₂Et) can undergo stoichiometric alkyne metathesis reactions. For example, reactions of Re{≡CCH₂(o-C₆H₄Br)}Cl₂(PMe₂Ph)₃ with TMSC≡CR (R = CO₂Et, CH₂Ph) and PhC≡CPh produced carbyne complexes Re(≡CR)Cl₂(PMe₂Ph)₃ and Re(≡CPh)Cl₂(PMe₂Ph)₃, respectively. Theoretical studies suggest that the metathesis reactions most likely proceed through six-coordinate alkyne-carbyne intermediates Re(≡CR)Cl₂(η²-alkyne)(PMe₂Ph)₂ that undergo reversible cycloaddition reactions.