反应详情

温度

20 °C

35.8 g (0.52 mol) of sodium methylate and 200 ml of toluene were put in a 750-ml sulfonation flask. The reaction mixture was heated to reflux temperature. A mixture of 55.7 g (0.33 mol) of 6-methyl nicotinic acid ethyl ester (produced according to Swiss Pat. No. 654 577) and 60.3 g (0.68 mol) of ethyl acetate was added drop by drop to the stirred suspension over 7 hour period. The suspension was stirred at reflux temperature for 22 hours and then cooled to 20° C. 200 ml of water and 25 ml of concentrated hydrochloric acid were added and the phases were separated. The water phase was extracted with toluene and the combined organic phases were evaporated. Then the evaporation residue was distilled under vacuum. 25.9 g of 6-methyl nicotinoyl acetic acid ethyl ester, having a boiling point of 112°-130° C./0.2-0.4 mbar and a content according to HPLC of 89.7 percent, was obtained (yield 33.6 percent, in relation to the 6-methyl nicotinic acid ethyl ester).

1. temperatureThe reaction mixture was heated
2. temperatureto reflux temperature
3. customproduced
4. temperatureat reflux temperature for 22 hours
5. customthe phases were separated
6. extractionThe water phase was extracted with toluene
7. customthe combined organic phases were evaporated
8. distillationThen the evaporation residue was distilled under vacuum
9. customwas obtained (yield 33.6 percent