Metalation-Induced Double Migration of Phosphorus from O-->C. Convenient Preparation of Bis(2-hydroxyaryl)phosphinic Acids

Article abstract of DOI:10.1021/jo00352a010

Treatment of diaryl ethyl phosphates 8 with lithium diisopropylamide in tetrahydrofuran yields ethyl bis(2-hydroxyaryl)phosphinates 9.The reaction involves the double migration of phophorus from O-->C and is probably intramolecular.These phosphinate esters 9 on treatment with trimethylsilyl chloride and sodium iodide in acetonitrile undergo transesterification to give trimethylsilyl esters that yield the corresponding phosphinic acids 15 on treatment with water.