Carbon-13 nuclear magnetic resonance spectra of polynuclear carbonyls of cobalt and rhodium

Abstract

A variable-temperature ¹³C n.m.r. spectroscopic study of the polynuclear carbonyls [Rh₂(η-C₅H₅)₂(CO)₃], [Rh₂(η-C₅H₅)₂(CO)₂(PR₃)], [Co₂(CO)₈], [Rh₄(CO)₁₂], [Rh₄(CO)₁₁(PPh₂R)](R = Ph or Me), [Co₄(CO)₁₂], [Co₄(C₆H₅Me)(CO)₉], [Co₄(RC₂R)(CO)₁₀], and [Rh₆(CO)₁₅1]^– has been carried out. Apart from [Co₂(CO)₈], [CO₄(RC₂R)(CO)₁₀], and [Co₄(CO)₁₂], solution geometries have been established. A variety of CO-fluxional mechanisms have been observed and are discussed.