Reactivity of a nucleophilic pyramidal phosphinidene complex with alkyl azides

Abstract

The study of the formation and reactivity of phosphinidene complexes is a very active area of current research in Organometallic Chemistry, partly because they are usually compared to carbenes.1 In order to deepen the knowledge and analyze the influence of ligand, we have synthesized and studied the chemical behavior of the complex [Mo2Cp(µ-κ1:κ1,h5-PC5H4)(h6-HMes*)(CO)2(PMe3)] (1), where the ligand adopts a pyramidal arrangement. Previous studies show its synthetic versatility and a highly nucleophilic behavior, for example in the reaction with BH3 and maleic anhidride.2 The reactions of the phosphinidenes with alkyl azides are very interesting for the different possibilities of coordination. They can give coordinated phosphatriazadiene ligands (RPN3R’), iminophosphinidene ligands (Staudinger reaction) and even N3P four-membered triazaphosphete complexes.3 Next scheme shows the most recent studies about the reactivity of complex 1 with this type of unsaturated molecules. The reaction with bencylazide has a special interest due to the big variety of compounds obtained, which has been characterized by single-cristal X-ray diffraction analysis, and they include the formation of chelate complexes and the loss of CO or N2, depending of the reaction conditions.