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

Participants

Reaction Conditions

Reaction Steps

Oxalyl chloride (9.0 mL, 100 mmol) was added to a solution of DMSO (10.5 mL, 150 mmol) in 80 mL of CH2Cl2 at −78° C., under a nitrogen atmosphere. The solution was stirred for 20 min at −78° C., tert-butyl (2R)-2-(hydroxymethyl)pyrrolidine-1-carboxylate (9.9 g, 49 mmol) was added, and the resultant solution stirred at −78° C. for 20 min. Triethylamine (28 mL, 200 mmol) was added to the reaction solution, the dry ice-acetone bath was removed, and the resultant solution was allowed to stir for two hours, slowly warming to ambient temperature. The reaction solution was quenched with brine, the phases were separated, and the organic phase was washed with 1 M KH2PO4 and saturated NaHCO3. The organic solution was then dried over Na2SO4, filtered, and concentrated to an orange oil. This oil was then dissolved in heptane, filtered through a plug of silica gel eluting with heptane, and the filtrate was concentrated to yield tert-butyl (2R)-2-formylpyrrolidine-1-carboxylate (7.87 g).

Provenance & Evidence