TRAPPING OF RADICALS IN THE COORDINATION SPHERES OF METALS

The use of hexamethylphosphoramide (HMPA) or other sterically demandin g groups as stabilizing ligands allows the successful isolation of a s eries of structurally characterizable complexes of ketyl radicals with alkali, alkaline earth, and lanthanide metal. It has been demonstrate d that the stability and reactivity of the ketyl radicals strongly dep end on both the nature of the metals to which they are bound and the s teric and electronic properties of the ancillary ligands, as well as t he structure of their parent ketones.