Hydrochloric Acid → HCID 86679299, compound

Participants

Reaction Conditions

Reaction Steps

To a solution of oxalyl chloride (319.4 mL of 2 M, 638.8 mmol) in CH2Cl2 (460 mL) is added DMSO (90.69 mL, 1.28 mol) over 30 minutes, keeping the internal temperature around-60° C. tert-Butyl (2S)-2-(hydroxymethyl)-4-methyl-pyrrolidine-1-carboxylate (55 g, 255.5 mmol) in CH2Cl2 (460 mL) is then added over 50 minutes at −78° C. The reaction mixture is stirred for 20 minutes before dropwise addition of DIPEA (445 mL, 2.55 mol). The reaction mixture is stirred at −78° C. for 2 hours and is allowed to warm to rt over 2 hours. To this mixture is added slowly 1N HCl (800 mL). After stirring, the organic phase is separated, dried over Na2SO4, filtered and concentrated to dryness. The residue is purified by flash column chromatography on silica gel (0 to 20% EtOAc in Hexanes) to give tert-butyl (2S)-2-formyl-4-methyl-pyrrolidine-1-carboxylate (48.5 g, 227.4 mmol, 85%) as a brown oil (mixture cis/trans 77/23).

Provenance & Evidence