Fast and Chemoselective Addition of Highly Polarized Lithium Phosphides Generated in Deep Eutectic Solvents to Aldehydes and Epoxides

Highly polarized lithium phosphides (LiPR2) have been synthesized, for the first time, in Deep Eutectic Solvents (DESs) as sustainable reaction media, at room temperature and in the absence of protecting atmosphere, through direct deprotonation of both aliphatic and aromatic secondary phosphines (HPR2) by n-BuLi. The subsequent addition of in-situ generated LiPR2 to aldehydes or epoxides proceeds fast and chemoselectively, thereby allowing the straightforward access to the corresponding α-hydroxy- or β-hydroxy phosphine oxides, respectively, under air and at room temperature (bench conditions), which are traditionally considered as textbookprohibited conditions in the field of polar organometallic chemistry of s-block elements.