反应详情

5-amino-2-methoxycarbonylmethyl-benzoic acid methyl ester (5 g, 22.4 mmol) was dissolved in hydrochloric acid (50 mL). To the solution was added dropwise aq.NaNO2 (1.7 g, 24.6 mmol) at below 5° C. After addition completed, the color became maroon. Then CuCl (2.4 g, 24.6 mmol) solution was added to the reaction mixture. The reaction mixture was reacted at below 5° C. for 1 hour. The reaction mixture was extracted with dichloromethane. The organic layer was washed with water, dried over anhydrous Na2SO4, concentrated and purified by column chromatography on silica gel (petroleum ether/ethyl acetate=10/1) to give 2.3 g of 5-chloro-2-methoxycarbonylmethyl-benzoic acid methyl ester (18E).

1. additionTo the solution was added dropwise aq
2. customat below 5° C
3. additionAfter addition
4. customThe reaction mixture was reacted at below 5° C. for 1 hour
5. extractionThe reaction mixture was extracted with dichloromethane
6. washThe organic layer was washed with water
7. dry with materialdried over anhydrous Na2SO4
8. concentrationconcentrated
9. custompurified by column chromatography on silica gel (petroleum ether/ethyl acetate=10/1)