(+)-1,4-Dihydro-5-isopropoxy-2-methyl-4-(2-trifluoromethylphenyl)-1,6-naphthyridine-3-carboxylic acid benzyl ester → (+)-1,4-Dihydro-5-isopropoxy-2-methyl-4-(2-trifluoromethylphenyl)-1,6-naphthyridine-3-carboxylic acid

Participants

Reaction Steps

1.6 g (0.00331 mole) (+)-1,4-dihydro-5-isopropoxy-2-methyl-4-(2-trifluoromethylphenyl)-1,6-naphthyridine-3-carboxylic acid benzyl ester is taken up in 32 mL ethanol and hydrogenated without the use of pressure at 20° C. in the presence of 0.64 g 10% palladium/charcoal (50% moist). The catalyst is filtered off and the filtrate evaporated to dryness at 35° C. on a rotary evaporator. The solid residue is recrystallized from 10 mL diisopropyl ether. The product is dried at 40° C. in a vacuum drying cabinet; yield: 1.04 g (80.3% of theory).

Provenance & Evidence