Diisopropylethylamine → N-methyl-3-{1-[2-(5-methyl-3-trifluoromethyl-pyrazol-1-yl)-acetyl]-piperidin-4-yl}-N-((R)-1-phenyl-ethyl)-benzamide

Participants

Reaction Steps

To a solution of 3-{1-[2-(5-methyl-3-trifluoromethyl-pyrazol-1-yl)-acetyl]-piperidin-4-yl}-benzoic acid (320 mg, 0.80 mmol) in DMF (8 mL) was added diisopropylethylamine (1.01 mL, 4.85 mmol), followed by 2-(1H-7-azabenzotriazol-1-yl)-1,1,3,3-tetramethyl uronium hexafluorophosphate methanaminium (0.41 g, 0.89 mmol) at RT. After stirring for 15 min. at RT, Methyl-((R)-1-phenyl-ethyl)-amine (0.132 g, 0.80 mmol) was added to the reaction mixture. After stirring for 2 h at RT, solvent was evaporated and the resulting brown oil was dissolved in ethylacetate (20 mL), washed with aq. sat. sodium bicarbonate solution (30 mL) and the aqueous phase was re-extracted with ethylacetate (20 mL). The combined organic layers were washed with 1M HCl solution (50 mL) and brine (50 mL), dried over sodium sulfate, filtered, and evaporated under reduce pressure. The crude mixture was purified by column chromatography on silica gel (ethylacetate/cyclohexane 1:1 to 8:2) to give N-methyl-3-{1-[2-(5-methyl-3-trifluoromethyl-pyrazol-1-yl)-acetyl]-piperidin-4-yl}-N—((R)-1-phenyl-ethyl)-benzamide (170 mg, 41%). 1H-NMR (400 MHz, d6-DMSO): δ=1.55 (d, 3H), 1.62-1.71 (m, 1H), 1.82-1.89 (m, 2H), 1.99 (s, 3H), 2.22 (s, 3H), 2.54-2.73 (m, 3H), 2.81-2.90 (m, 1H), 3.12-3.21 (m, 1H), 3.99-4.04 (m, 1H), 4.46-4.52 (m, 1H), 5.19-5.38 (m, 2H), 6.50 (s, 1H), 7.12-7.41 (m, 9H). MS: m/z=513 (M+1)

Provenance & Evidence