Synthesis, protonation, and electrophilic reactions of Tp′(CO)2WCOMe, a tungsten methoxycarbyne complex

The synthesis and characterization of the terminal methoxycarbyne complex Tp′(CO)2WCOMe is described. Nucleophiles attack Tp′(CO)2WCOMe at the methyl group of the methoxide substituent. The carbyne complex undergoes reversible protonation at the carbyne carbon in the presence of [H(Et2O)2][BAr′4] to generate the α-agostic carbene complex [Tp′(CO)2WC(H)OMe][BAr′4].