Highly Chemoselective Transformation of Secondary Propargylic Alcohols with (EtO)2P(O)SH

Abstract A practical and environmentally friendly approach is presented for the efficient construction of propargyl organothiophosphates and allenyl organothiophosphates from easily prepared secondary propargylic alcohols and O , O ‐diethyl phosphorothioic acid [(EtO) 2 P(O)SH]. The reaction proceeds smoothly in moderate to excellent yields without additional acid promoters or additives under mild conditions with water as the only by‐product. The divergent products are selectively obtained depending on substrates bearing different substituents on the aromatic ring. Notably, the developed reaction system can be scaled up to gram quantities.