Structural and EPR characterisation of single electron and alkyl transfer products from reaction of dimethyl magnesium with bulky alpha-diimine ligands

摘要

Treatment of dimethylmagnesium with bulky alpha-dlimine ligands provides either the biradical methyl-bridged complexes [(alpha-diimine~(- centre dot))Mg~+(mu-CH_3)]_2 via single electron transfer (SET), or the product of methyl transfer to an imine carbon atom depending upon conditions.Chclating ligands containing the alpha-diimine unit [RN=C(R)C(R)=NR],of the polypyridine(e.g.2,2'-bipyridine,1,10-phenanthroline)and 1,4-diazabutadiene2 form,are among the most widely employed nitrogen donor ligands in coordination chemistry.Their alpha-donor characteristics coupled with the accessibility and symmetry properties of the pi* molecular orbitals result in their compatibility with both main group and transition