反应详情

To a solution of 1-tert-butyl 4-ethyl 4-((3-iodo-1-isopropyl-1H-pyrazol-4-yl)methyl)piperidine-1,4-dicarboxylate (455 mg, 0.9 mmol) in methanol (20 mL) was added 2 N NaOH (5 mL). After stirring for 18 hours at room temperature, the methanol was removed under reduced pressure and the resultant slurry was taken up in 20 mL water, acidified with 2 N HCl and extracted with ethyl acetate (2×30 mL). The combined organic extracts were dried over sodium sulfate, filtered and concentrated to yield 1-(tert-butoxycarbonyl)-4-((3-iodo-1-isopropyl-1H-pyrazol-4-yl)methyl)piperidine-4-carboxylic acid (430 mg) as a colorless solid. −APCI (M−H) 476.1; 1H NMR (400 MHz, CDCl3, δ): 7.11 (s, 1H), 4.45 (dquin, J=13.4, 6.7 Hz, 1H), 3.95 (br. s., 2H), 2.91 (m, 2H), 2.69 (s, 2H), 2.08 (m, 2H), 1.47 (m, 8H).

1. customthe methanol was removed under reduced pressure
2. extractionextracted with ethyl acetate (2×30 mL)
3. dry with materialThe combined organic extracts were dried over sodium sulfate
4. filtrationfiltered
5. concentrationconcentrated