Nitrosyl complexes of molybdenum and tungsten

Abstract

Molybdenum pentachloride in benzene reacts with nitrogen oxide to form a red nitrosyl from which a series of mononitrosyl complexes of molybdenum can be synthesised, including [MoCl₄(NO)]^–, [MoCl₅(NO)]^2–, [MoCl₃(NO)L₂], [MoCl₄(NO)L]^–, [MoCl₃(NO)L₃], [MoCl₃(NO)L₂]^–, [MoCl₂(NO)L₃], and [MoCl(NO)L₄](L = neutral ligand). The co-ordinated NO in these complexes shows no sign of reactivity with nucleophiles or with electrophiles although the original red nitrosyl is apparently converted by some tertiary phosphines into amido- and phosphineiminido-complexes. Some tungsten analogues are also described.