Simple Preparation of (2,2′-Biphenylylene)phenylphosphine Oxide and Role of Triphenylphosphine Oxide as a Mediator for Formation of Biaryl Derivatives

Abstract

Abstract (2,2′-Biphenylylene)phenylphosphine oxide (3) was prepared simply by the reaction of triphenylphosphine oxide (1) with phenyllithium and subsequently with aqueous hydrogen peroxide in acetic acid. The oxide 3 reacted with lithium diisopropylamide (LDA) and then with several electrophiles to afford regiospecifically ortho-substituted compounds in moderate yields, which were converted to unsymmetrical 2-and 2,3′-substituted 1,1′-biaryls and triphenylphosphine oxide (1).