Regioselective One-Pot Synthesis of Vicinal Bisphosphine Derivatives from Nitroalkenes by Hydrophosphinylation/Elimination/Hydrophosphinylation

Synthesizing Chiral Vicinal Bisphosphine Derivatives through Hydrophosphinylation and Asymmetric Protonation of Secondary Phosphine Sulfides with Vinylphosphine Oxides

Herein, we report bifunctional iminophosphorane-catalyzed hydrophosphinylation and asymmetric protonation of secondary phosphine sulfides with vinylphosphine oxides. This reaction efficiently afforded chiral vicinal bisphosphine derivatives in high yields with excellent enantioselectivities (up to 99% yield and 95% ee). Furthermore, the produced chiral vicinal bisphosphine derivatives could be readily transformed into vicinal bisphosphines and vicinal bisphosphine monosulfides. This study presents the first methodology for using secondary phosphine sulfides as pronucleophiles in asymmetric protonation reactions.

Dithiophosphinylation of Allenyl Acetates: Access to 1,2-Bis(diphenylphosphino)ethane-Type Bidentate Ligands

1,2-Bis(diphenylphosphino)ethanes (DPPEs) are versatile and immensely important ligands in transition metal catalysts. Here we report the dithiophosphinylation of readily available allenyl acetates to give DPPEs in high yields and regioselectivity. This protocol features a broad substrate scope and mild conditions, avoiding the use of transition metals and air-sensitive sources of phosphorus. Mechanism studies indicate that the reaction was accomplished via an SN2'-type addition-elimination followed by a 1,4-addition step.