反应详情

3 g (11.4 mmol) of tert-butyl 3-hydroxy-3-o-tolylazetidine-1-carboxylate in 20 ml of N,N-dimethylformamide are added dropwise to a suspension of 1.4 g of sodium hydride at 60% in oil (34.2 mmol) in 14 ml of N,N-dimethylformamide, precooled to 0° C. After stirring for 20 minutes, 1 ml of bromomethylcyclopropane (11.4 mmol) is added and stirring is continued for 1 hour 30 minutes. The reaction medium is hydrolysed with saturated aqueous ammonium chloride solution and then extracted with a 1/1 heptane/ethyl acetate mixture. The organic phase is washed with saturated aqueous sodium chloride solution, dried over sodium sulfate, filtered and concentrated under vacuum. 4 g of crude residue are obtained and are purified by chromatography on silica gel eluted with a heptane/ethyl acetate mixture, the polarity being increased from 95/5 to 80/20. 2.9 g (81%) of tert-butyl 3-cyclopropylmethoxy-3-o-tolylazetidine-1-carboxylate are obtained in the form of a yellow oil.

1. customprecooled to 0° C
2. stirringstirring
3. waitis continued for 1 hour 30 minutes
4. extractionextracted with a 1/1 heptane/ethyl acetate mixture
5. washThe organic phase is washed with saturated aqueous sodium chloride solution
6. dry with materialdried over sodium sulfate
7. filtrationfiltered
8. concentrationconcentrated under vacuum
9. custom4 g of crude residue are obtained
10. customare purified by chromatography on silica gel
11. washeluted with a heptane/ethyl acetate mixture
12. temperaturethe polarity being increased from 95/5 to 80/20