Facile synthesis of chelating bisphosphine oxides and bisphosphines via palladium-catalyzed bishydrophosphinylation reactions

A series of functional bisphosphosphine oxides were synthesized in good yields via new Pd-catalyzed bis-hydrophosphinylation reactions of terminal alkynes and diphenylphosphine oxide. The resulting bisphosphine oxides were reduced to their corresponding bisphosphines in quantitative yields via a Ti(OiPr)4-mediated process.