Synthesis, characterization and Schlenk equilibrium studies of methylmagnesium compounds with O- and N-donor ligands - the unexpected behavior of [MgMeBr(pmdta)] (pmdta = N,N,N′,N″,N″-pentamethyldiethylenetriamine)

Syntheses and temperature dependent NMR studies of some methylmagnesium complexes with different O- and N-donors L (L = thf, diglyme, NEt3, tmeda, dabco, pmdta) give insight into the influence of the co-ligand L on the position of the Schlenk equilibrium showing that in thf the equilibrium I (pmdta = N,N,N′,N″,N″-pentamethyldiethylenetriamine) lies completely on the left side.