3-Boc-2,2-dimethyloxazolidine-4-carboxaldehyde, (R)-(+)- → tert-Butyl (4S)-4-ethynyl-2,2-dimethyl-1,3-oxazolidine-3-carboxylate

Participants

Reaction Steps

(S)-N-Boc-2,2-dimethyl-4-ethynyl-oxazolidine was prepared according to Method X above by the treatment of tert-butyl-(R)-4-formyl-2,2-dimethyl-3-oxazolidine-carboxylate (1.00 g, 4.36 mmol) (Aldrich) with potassium tert-butoxide (730 mg, 6.54 mmol) and diazomethyl-phosphonic-acid-diethylester (1.20 g, 6.54 mmol) (Method X above). The reaction was allowed slowly to warm up to room temperature and stirred for a total of 12 hrs. (S)-N-Boc-2,2-dimethyl-4-ethynyl-oxazolidine was obtained after silica gel column chromatography with 20% Et2O in hexanes. (Yield 420 mg, 43%).

Provenance & Evidence