Nucleophilic displacement at terminal chloromethylidyne ligands. New synthetic routes to organothio-, organoseleno-, and organotelluro-methylidyne and carbon monosulphide, monoselenide, and monotelluride complexes of molybdenum: X-ray crystallographic characterisation of η1-p-nitrophenylthiomethylidyne(dicarbonyl)[hydrotris(3,5-dimethylpyrazol-1-yl)borato]molybdenum(IV)

Abstract

Nucleophilic displacement at the carbon atom of a terminal methylidyne ligand has been observed for the first time in the reaction of [Mo(η¹-CCl)(CO)₂(L)][L = hydrotris(3,5-dimethylpyrazol-1-yl)borato]with RE^–(E = S, Se) and E^2–(E = S, Se, Te); the products isolated include the organothiomethylidyne complex [Mo(µ¹-CSC₆H₄NO₂-p)(CO)₂(L)](which has been characterised by X-ray crystallographic methods), the first organoselenomethylidyne complex [Mo(η¹-CSeC₆H₅)(CO)₂(L)], and the first Group 6B carbon monotelluride complex [Mo(CTe)(CO)₂(L)]^– which is turn has been converted into [Mo(η¹-CTeMe)(CO)₂(L)], the first organotelluromethylidyne complex.