Triphenylphosphine → (R)-tert-butyl 4-((1R,2S)-3-azido-1-(tert-butyldimethylsilyloxy)-2-methylpropyl)-2,2-dimethyloxazolidine-3-carboxylate

Participants

Reaction Steps

To a solution of (R)-tert-butyl 4-((1R,2S)-1-(tert-butyldimethyl-silyloxy)-3-hydroxy-2-methylpropyl)-2,2-dimethyloxazolidine-3-carboxylate (1.0 equiv.), DIAD (2.0 equiv.), and PPh3 (2.0 equiv.) in THF (0.18 M) was added DPPA (2.0 equiv., 1M solution in THF). The reaction mixture was stirred at room temperature overnight. Upon removal of the volatiles under vacuo, the residue was purified by silica gel column chromatography eluting with ethyl acetate and hexanes (1:6) to give (R)-tert-butyl 4-((1R,2S)-3-azido-1-(tert-butyldimethylsilyloxy)-2-methylpropyl)-2,2-dimethyloxazolidine-3-carboxylate as the major product (5:2) in 86% yield. LC/MS=329.3 (M+H-Boc), Rt=1.40 min (Frac 65%-95% method).

Provenance & Evidence