Diastereospecific synthesis of β-heterosubstituted alcohols from 1,2-diols via 1,3,2λ5-dioxaphospholanes

The stereochemistry of the ring opening of (R,S) or (R,R)-4,5-dimethyl-2,2,2-triphenyl-1,3,2λ⁵-dioxaphospholanes (prepared by reaction of (R,S) or (R,R)-butane-2,3-diol with dibromotriphenylphosphorane) by aniline or thiophenol was investigated. The reaction affords stereoselectively the corresponding β-anilino- or β-phenylthioalcohols with a nearly complete inversion of stereochemistry at the stereogenic reaction centre.