Mechanism of alkylation and acylation of dinitrogen co-ordinated to molybdenum and tungsten

Abstract

The alkylation, acetylation, and aroylation reactions of [M(N₂)₂(dppe)₂](M = MO or W; dppe = Ph₂PCH₂CH₂PPh₂) by organic halides RX are shown to procede by the initial rate-determining dissociation of one N₂ from the complex to form [M(N₂)(dppe)₂], addition of the halide through the halogen to the metal producing an un-stable intermediate, [M(N₂)(RX)(dppe)₂], homolysis of the carbon-halogen bond, and attack of the organic free radical generated on the remaining co-ordinated N₂ to produce [Mo(N₂R)X(dppe)₂].