反应详情

To a solution of methyl-(2-methyl-5-pyridin-3-yl-2H-pyrazol-3-yl)-amine (150 mg, 0.8 mmol) under N2 in ice-cold dichloroethane (DCE; 2 mL) was added dropwise via pipette a solution of 2-methyl-3-methylsulfanyl-propionylchloride (146 mg, 0.9 mmol) in DCE (1.5 mL). After stirring for 10 minutes (min), a solution of 4-N,N-dimethylaminopyridine (DMAP; 107 mg, 0.9 mmol) in DCE (2 mL) was added dropwise. The ice bath was removed after 30 min, and the mixture was stirred at room temperature for 90 min and then at reflux for 14 h. The mixture was concentrated under reduced pressure and was purified by silica gel chromatography eluting with a gradient of EtOAc in hexane. The product, 2,N-dimethyl-N-(2-methyl-5-pyridin-3-yl-2H-pyrazol-3-yl)-3-methylsulfanyl-propionamide, was isolated as a yellow semi-solid (44 mg, 24%): 1H NMR (400 MHz, CDCl3) δ 9.00 (s, 1H), 8.58 (s, 1H), 8.08 (br d, J=7.0 Hz, 1H), 7.35 (br dd, J=7.3, 4.8 Hz, 1H), 6.58 (br s, 0.5H), 6.49 (br s, 0.5H), 3.89-3.79 (m, 3H), 3.25 (s, 3H), 2.96-2.80 (m, 1H), 2.42-2.40 (m, 1H), 2.02-1.99 (m, 3H), 2.62 (m, 1H), 1.15 (d, J=6.0 Hz, 3H); MS (m/z) 305.0 [M+1].

1. customThe ice bath was removed after 30 min
2. stirringthe mixture was stirred at room temperature for 90 min
3. temperatureat reflux for 14 h
4. concentrationThe mixture was concentrated under reduced pressure
5. customwas purified by silica gel chromatography
6. washeluting with a gradient of EtOAc in hexane