4-Vinylpyridine complexes of group VIB metals: Syntheses, reactions and spectral features

Abstract

Reactions of [M(CO)₆) or [M(CO)₃(MeCN)₃] (M=Cr, Mo or W) with 4-vinylpyridine lead to the complexes having the formulation [(4-CH₂= CH-C₅H₄N)M(CO)₃] (<strong>I</strong>) in which 4-vinylpyridine is bonded to the metal atom through the six π-electrons of the heteroaromatic ring. Reaction of <strong>I</strong> (M = Cr) with HCl gas affords the N-protonated complex [4-CH₂= CH-C₅H₄NH)Cr(CO)₃ Cl(<strong>II</strong>). Complexes (<strong>I</strong>) (M=Cr or Mo) also react with PPh₃to give[M(CO)₃(PPh₃)₃] (<strong>III</strong>).