Notes. Further comments on one-electron oxidation versus nitrosyl complex formation during the reactions of the nitrosyl cation with metal carbonyl derivativest

Abstract

The cation [NO]⁺ reacts with [M(CO)₄(L–L)][1 : M = Cr, Mo, or W; L–L = Ph₂PCH₂CH₂PPh₂(dppe) or Ph₂PCH₂PPh₂, (dppm)] to give [M(CO)₃(NO)(L–L)]⁺(2) or, when NO is removed from the reaction mixture, [M(CO)₄(L–L)]⁺(3; M = Cr). A modification is therefore made to the mechanism previously proposed for the reactions of [NO]⁺ with metal carbonyl derivatives, [ML_n], such that the intermediate adduct [ML_n(NO)]⁺ is in equilibrium with [ML_n]⁺ and NO radicals. The isolation of the acid–base adducts [Ag{M(CO)₄(L–L)}₂]⁺(4; M = Mo or W, L–L = dppe or dppm), from the reaction of (1) with Ag⁺ ions, is indirect evidence tor the formation of seven-co-ordinate intermediates, [M(CO)₄(NO)(L–L)]⁺, in the reactions between (1) and [NO]⁺.