Transition metal complexes of substituted alkynes. V. Compounds derived from Tri- and Tetra-cobalt carbonyl complexes

Abstract

Treatment of dodecacarbonyltetracobalt with several fluorocarbon alkynes has given complexes of stoicheiometry Co₄(CO)₁₀,(alkyne). For comparison, analogous complexes of the related hydrocarbon alkynes have also been prepared. Infrared, nuclear magnetic resonance, and mass spectra of the complexes are given and the probable structure of the complexes deduced. The reaction of both fluorocarbon and hydrocarbon alkynes with the cluster carbonyl compounds Co₃(CO)₉CY (Y = CH₃, C₆H₅, CO₂CH₃) has also been investigated. The products obtained in these reactions include substituted benzenes and the two organocobalt complexes Co₂(CO)₆(alkyne) and Co₂(CO)₄(alkyne)₃. The probable mode of formation of these compounds is discussed. The role played by the various complex types in the reactions of alkynes with cobalt carbonyls is also considered.