反应详情

To a solution of pyrrolidine-1-carboxylic acid 4-hydroxycyclohexylmethyl ester (2 mmol) in methylene chloride (10 mL) were added TEMPO (0.2 mmol), tetrabutylammonium bromide (0.8 mmol), and oxone (4.4 mmol) and the resulting mixture was stirred for 14 hours. The reaction mixture was diluted with water, followed by few times of extraction with methylene chloride. The combined organic layer was dried over anhydrous magnesium sulfate, filtered and concentrated under reduced pressure. The residue was purified by column chromatography (silica gel, hexane:ethyl acetate=1:2) to provide pyrrolidine-1-carboxylic acid 4-oxo-cyclohexylmethyl ester. To a solution of pyrrolidine-1-carboxylic acid 4-oxo-cyclohexylmethyl ester in 1,2-dichloroethane (10 mL) were added benzyl amine (2 mmol) and sodium triacetoxyborohydride (2 mmol) and the resulting mixture was stirred for 14 hours. The reaction mixture was diluted with water, followed by few times of extraction with methylene chloride. The combined organic layer was dried over anhydrous magnesium sulfate, filtered and concentrated under reduced pressure. The residue was purified by column chromatography (silica gel, ethyl acetate), thereby completing the preparation of a target compound (399 mg, 63% yield). To a solution of the obtained compound in methylene chloride was added a saturated HCl solution in ether to provide a hydrochloride salt.

1. extractionfollowed by few times of extraction with methylene chloride
2. dry with materialThe combined organic layer was dried over anhydrous magnesium sulfate
3. filtrationfiltered
4. concentrationconcentrated under reduced pressure
5. customThe residue was purified by column chromatography (silica gel, hexane:ethyl acetate=1:2)