Ammonia → (2R,3S)-N-tert-Butyloxycarbonyl-3-(tert-butyldimethylsilanyloxy)-2-((1S)-1-aminoethyl) pyrrolidine

Participants

Reaction Steps

To a solution of 61E (3.6 g, 10.0 mmol) in methanol in a pressure vessel was added Raney Ni in water (˜0.2 g), 10% Pd/C (Degussa type, 200 mg), water (7.5 mL) and ammonia in methanol (2.0 M, 5 mL). The reaction vessel was carefully evacuated under vacuum until the solvent bubbled gently. Hydrogen gas was then introduced to a pressure of 70 psi and the reaction was stirred for 2 min). The reaction vessel was again carefully evacuated under vacuum until the solvent bubbled gently. Hydrogen gas was then introduced to a pressure of 70 psi and the reaction was stirred for 18 h at rt. The reaction was filtered through a pad of celite, taking care to keep the captured catalyst wet with methanol at all times. The celite pad was washed with methanol until the product could no longer be detected in the eluent (TLC, 5% MeOH in CH2Cl2, stain with ninhydrin and heat). Solvent was removed under vacuum and purification by flash chromatography (110 g ISCO silica gel cartridge, step gradient 0%-5%-10% MeOH in CH2Cl2) gave the title compound (2.2 g): MS (ES) m/z 345.35 [M+H]+

Provenance & Evidence