Sodium borohydride → (S)-N-((3aS,4S,6aR)-2-benzyloctahydrocyclopenta[c]pyrrol-4-yl)-2-methylpropane-2-sulfinamide

Participants

Reaction Conditions

Reaction Steps

A mixture of (S,E)-N-((3aS,6aR)-2-benzylhexahydrocyclopenta[c]pyrrol-4(5H)-ylidene)-2-methylpropane-2-sulfinamide (0.940 g, 2.95 mmol) from Step A in methanol (20 mL) was cooled to −78° C. in a dry ice/acetone bath. Sodium borohydride (0.335 g, 8.85 mmol) was added, and the reaction was allowed to warm to room temperature overnight. The reaction was quenched with saturated aqueous ammonium chloride, diluted with water, and extracted with 3×100 mL of ethyl acetate. The extracts were dried (Na2SO4) and filtered. The solvent was removed in vacuo, and the crude material was chromatographed using a silica gel cartridge (Analogix®, Burlington, Wis., RS-40) with 5-50% acetone/hexanes to give (S)—N-((3aS,4S,6aR)-2-benzyloctahydrocyclopenta[c]pyrrol-4-yl)-2-methylpropane-2-sulfinamide: 1H NMR (300 MHz, CDCl3) δ ppm 7.37-7.11 (m, 5H), 4.85 (d, J=7.0, 1H), 3.90-3.71 (m, 2H), 3.28 (d, J=13.0, 1H), 3.09 (d, J=9.8, 1H), 2.72-2.50 (m, 2H), 2.46 (d, J=9.6, 1H), 2.32-2.12 (m, 2H), 1.82 (td, J=5.5, 12.7, 1H), 1.68-1.60 (m, J=10.6, 2H), 1.35-1.24 (m, 1H), 1.20 (s, J=5.5, 9H).

Provenance & Evidence