Hydroperoxide-Initiated Intramolecular Insertions of NO into Metal−Carbon Bonds

Abstract

The chemical transformations of metal-bound NO groups (i.e., nitrosyl ligands) have attracted considerable attention because of both their fundamental significance and their possible biological and environmental relevance. We now report our novel discovery that an oxygen-atom transfer reagent can initiate the subsequent intramolecular insertion of bound NO into an adjacent metal−ligand bond. Specifically, we have demonstrated that treatment of the dialkyl compounds Cp*Mo(NO)(CH 2 CMe 3 ) 2 ( 1 ) and Cp*W(NO)(CH 2 SiMe 3 ) 2 ( 3 ) (Cp* = η 5 -C 5 Me 5 ) with cumene hydroperoxide induces the insertion of NO into one of their metal−carbon bonds and results in the clean formation of the η 2 -nitrosoalkane oxo complexes Cp*Mo(O)(η 2 -ONCH 2 CMe 3 )(CH 2 CMe 3 ) ( 2 ) and Cp*W(O)(η 2 -ONCH 2 SiMe 3 )(CH 2 SiMe 3 ) ( 4 ). Further treatment of complexes 2 and 4 with excess O 2 results in liberation of the nitroalkanes O 2 NCH 2 EMe 3 (E = C, Si) from the metals’ coordination spheres and formation of the dioxo alkyl complexes Cp*Mo(O) 2 (CH 2 CMe 3 ) ( 5 ) and Cp*W(O) 2 (CH 2 SiMe 3 ) ( 6 ).