Stabilization of Hydroxy Tautomeric Form of Dimethyl Phosphite in the Coordination Sphere of Carbonyl Complexes of Group VI Metals

Abstract

The interaction of dimethyl phosphite with hexacarbonyls of the chromium group metals in a nonpolar solvent has afforded metal(0) σ⁴,λ⁴-(dimethyl phosphite)pentacarbonyls containing a hydroxy tautomeric form of dimethyl phosphite in the coordination sphere. Hydrogen of the phosphite OH group in the metal(0) σ⁴,λ⁴-(dimethyl phosphite)pentacarbonyls exhibited a significant acidity, strongest for the chromium complexes. Due to the significant acidity of the phosphite hydroxyl, the metal(0) σ⁴,λ⁴-(dimethyl phosphite)-pentacarbonyls are intermediates in the electrophilic version of the Pudovik reaction.