反应详情

Oxalyl chloride (7.5 ml, 85 mmol) was added dropwise to a stirred solution of cyclopentanecarboxylic acid (4.56 g, 40 mmol) and dimethylformamide (2 drops) in dichloromethane (20 ml) under nitrogen at room temperature. After 2 hours, the reaction mixture was evaporated under reduced pressure and the residual oxalyl chloride removed azeotropically using dichloromethane. The resulting oil was dissolved in dichloromethane (50 ml) and N,O-dimethylhydroxylamine (4.3 g, 44 mmol) added portionwise to the stirred solution. The resulting mixture was cooled using an ice bath, pyridine (7.1 ml, 88 mmol) added, the cooling bath removed and stirring continued for 18 hours. The reaction mixture was then diluted with dichloromethane (50 ml), washed with 5% aqueous citric acid solution (×2) and saturated brine, dried (Na2SO4) and evaporated under reduced pressure. The residue was purified by chromatography on silica gel, eluting with a solvent gradient of methanol:dichloromethane (0:100 to 2:98), to furnish the required amide as an oil. Rf 0.50 (SS 18). Found: C,59.28; H,9.74; N,8.81. C8H15NO2 ; 0.25 H2O requires C,59.41; H,9.66; N,8.66%.

1. customthe reaction mixture was evaporated under reduced pressure
2. customthe residual oxalyl chloride removed azeotropically using dichloromethane
3. dissolutionThe resulting oil was dissolved in dichloromethane (50 ml)
4. temperatureThe resulting mixture was cooled
5. customthe cooling bath removed
6. waitcontinued for 18 hours
7. additionThe reaction mixture was then diluted with dichloromethane (50 ml)
8. washwashed with 5% aqueous citric acid solution (×2) and saturated brine
9. dry with materialdried (Na2SO4)
10. customevaporated under reduced pressure
11. customThe residue was purified by chromatography on silica gel
12. washeluting with a solvent gradient of methanol:dichloromethane (0:100 to 2:98)