The synthesis of macrocyclic diphosphines is described. Diisopropyl polymethylenediphosphinates were obtained from Michaelis-Arbuzov reaction of diisopropyl phenylphosphonite and polymethylene dibromides. Subsequent reaction of diisopropyl polymethylenediphosphinate with polymethylene dibromide in the presence of sodium bis (2- methoxyethoxy) aluminum hydride under high dilution condition afforded two isomeric ...
