Diisopropylethylamine → tert-butyl (2S)-2-formylpyrrolidine-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

A mixture of 3 (11.80 g, 38.8 mmol), N-Boc-L-Pro-OH (10.02 g, 46.6 mmol), and diisopropylethylamine (7.02 g, 54.3 mmol) in acetonitrile (200 mL) was stirred at 50° C. for 10 h. The solvent was evaporated and the residue was partitioned between methylene chloride and H2O. The organic layer was separated and concentrated to dryness. The crude product was purified by silica gel column chromatography (hexanes/ethyl acetate=1/7 to 1/4 (v/v)) to provide 4 (11.53 g, 68% yield) as a white solid. 1H NMR (CDCl3, 400 MHz) δ 7.84 (m, 1H), 7.48 (m, 2H), 5.58 (m, 1H), 4.40 (m, 1H), 3.60 (m, 1H), 3.40 (m, 1H), 3.18 (m, 1H), 3.04 (m, 1H), 2.37 (m, 2H), 2.04 (m, 1H), 1.96 (m, 1H), 1.46 (ds, 9H) ppm.

Provenance & Evidence