(Diethylamino)sulfur trifluoride → 3-Fluoroproline

Participants

Reaction Steps

To a solution of the 3-hydroxyproline methyl ester in DCM at −78° C., DAST (4 eq.) was added dropwise with stirring. The reaction was slowly warmed to rt. It was stirred at rt for 16 h, then diluted with more DCM and washed with cold saturated sodium bicarbonate, dried over sodium sulfate, filtered, concentrated and purified by column chromatography (SiO2, 20-30% ethyl acetate/hexanes) to provide the desired 3-fluoroproline intermediate.

Provenance & Evidence