Dimethyl Sulfoxide → N-(tert-Butoxycarbonyl)-D-prolinal

Participants

Reaction Steps

Oxalyl chloride (12.0 ml, 0.14 mol) was added dropwise with stirring to methylene chloride (200 mL) at -78° C., under nitrogen. Ten min. after addition was complete, DMSO (20 mL) was slowly added and stirring was continued for an additional 10 min. (R)-t-Butyl 2-(hydroxymethyl)-1-pyrrolidinecarboxylate (15.0 g, 0.075 mol) in methylene chloride was added to the stirred solution and after 30 min triethylamine (56 mL) was added. The solution was held at -78° C. for 30 min. and was then allowed to warm to room temperature. Water (100 mL) was added, the phases separated, and the aqueous phase reextracted with methylene chloride (200 mL). The combined organic phases were washed with water (30 mL), evaporated, and the residual oil was chromatographed on silica gel using ethyl acetate:Skellysolve B (1:2) as eluant to give 14.2 g (95%) of product.

Provenance & Evidence