4-[(R)-3-(3,5-dichloro-phenyl)-4,4,4-trifluoro-3-nitromethyl-butyryl]-2-methyl-benzoic acid tert-butyl ester → 4-[(R)-4-(3,5-dichloro-phenyl)-4-trifluoromethyl-4,5-dihydro-3H-pyrrol-2-yl]-2-methyl-benzoic acid tert-butyl ester

Participants

Reaction Steps

Alternatively, the title compound can be obtained by carrying out the following experiment: To a vigorously stirred solution of 4-[(R)-3-(3,5-dichloro-phenyl)-4,4,4-trifluoro-3-nitromethyl-butyryl]-2-methyl-benzoic acid tert-butyl ester (100 mg) in ethanol (6 mL) was added Raney Nickel (1.44 g, 50% suspension in water, previously washed with dry ethanol) and the reaction was stirred at room temperature under hydrogen (1 atm) for one hour. Then the solution was filtered over celite, and the resulting filtrate was concentrated in vacuo to give the title compound (78 mg) as a pale yellow solid. Chiral HPLC analysis (Chiralpack IA, Heptane:2-propanol:diethylamine=90:10:0.1, 1 ml/min, retention time 5.77 minutes (91.43%), 8.71 minutes (3.79%).

Provenance & Evidence