Acetic Acid → tert-butyl (2R,5R)-5-[(benzylamino)methyl]-2-[2-(2-{[N-(methoxycarbonyl)-beta-phenyl-L-phenylalanyl]amino}phenyl)ethyl]morpholine-4-carboxylate

Participants

Reaction Steps

To a solution of tert-butyl (2R,5S)-5-formyl-2-[2-(2-{[N-(methoxycarbonyl)-b-phenyl-L-phenylalanyl]amino}phenyl)ethyl]morpholine-4-carboxylate (1 eq.) in MeOH (0.05 M) was added benzylamine (7 eq.), magnesium sulfate (1.2 eq.) and acetic acid (7 eq.). The solution was stirred for 30 minutes and sodium cyanoborohydride (2.3 eq.) was added and the reaction mixture was further stirred for 2 hours. The reaction mixture was then quenched by the addition of aqueous sodium bicarbonate and the aqueous layer was extracted with ethyl acetate three times. The combined organic layers were washed with water, dried over Na2SO4, filtered and concentrated. The residue was purified by automated silica gel flash chromatography system eluted with a gradient 30% to 100% of EtOAc/Hex to afford title compound.

Provenance & Evidence