3-Nitro-5-(trifluoromethyl)benzoic acid → 3-Amino-5-(trifluoromethyl)benzoic acid

Participants

Reaction Steps

A solution of 3-nitro-5-(trifluoromethyl)benzoic acid (5.4 g, 23 mmol) in MeOH (115 mL) was charged with 5% Pd/C, Degussa (1.09 g). The reaction vessel was purged with hydrogen and stirred under a hydrogen atmosphere (1 atm) for 3 h. The mixture was filtered and the filtrate was concentrated in vacuo to provide 3-amino-5-(trifluoromethyl)benzoic acid (4.25 g). This material was incorporated into procedure (80a) to provide 3-benzylamino-5-(trifluoromethyl)benzoic acid, a portion (17 mg, 0.06 mmol) of which was incorporated into procedure (91b). Purification by RP-HPLC afforded the title compound (S)-1.5 (R1=2,4-dimethylphenyl, R3=—C(O)NHt-Bu, Z=—C(O)—, R2=3-benzylamino-5-(trifluoromethyl)phenyl, all other R=H; 3 mg). Exact MS calcd for C33H41F3N5O3, the formula for (M+H)+=612.3161. Found: 612.3184.

Provenance & Evidence