4-Methylmorpholine → HCID 14821719, compound

Participants

Reaction Steps

To a solution of (2S,4R)-4-(benzyloxy)-1-(tert-butoxycarbonyl)pyrrolidine-2-carboxylic acid (5.00 g, 15.56 mmol) in tetrahydrofuran (50 mL) at −10° C. was added N-methylmorpholine (1.882 mL, 17.11 mmol). To this solution was added slowly isobutyl chloroformate (2.34 g, 2.25 mL, 17.11 mmol). The resulting mixture was stirred for 30 minutes and filtered, and the filtrate was added to a solution of sodium borohydride (1.18 g, 31.1 mmol) in water (1.5 mL) at 0° C. The resulting mixture was stirred at 0° C. for 30 minutes, and the reaction was quenched by the addition of a saturated solution of NH4Cl. The mixture was extracted with ethyl acetate, and the organic extract was washed with brine, dried with MgSO4, filtered, and concentrated in vacuo. The crude product was purified by column chromatography on silica gel using a solvent gradient of 0-2% methanol in dichloromethane to give the title compound as a colorless oil (3.93 g, 82%). 1H NMR (400 MHz, pyridine-d5, 90° C.) δ ppm 7.36 (d, J=7.4 Hz, 2 H), 7.30 (t, J=7.3 Hz, 2 H), 7.23 (t, J=7.2 Hz, 1 H), 4.50 (s, 2 H), 4.20-4.29 (m, 2 H), 3.92-4.00 (m, 1 H), 3.80-3.87 (m, 2 H), 3.50-3.59 (m, 1 H), 2.16-2.30 (m, 2 H), 1.47 (s, 9 H).

Provenance & Evidence