反应详情

温度

-20 °C

A solution of 68 g of p-chlorobromobenzene in 150 cc of ether was added under an inert atmosphere to 250 cc of a solution of 1.4 N butyl lithium in hexane cooled to -20° C. and after stirring for 2 hours, the temperature was allowed to rise to room temperature. A solution of 28.6 g of 3-cyano-2-methylbenzoic acid in 300 cc of tetrahydrofuran was added to the solution of the lithium compound cooled to -60° C. and then the temperature was allowed to return to room temperature and remain there overnight. The reaction mixture was added to a water-ice mixture and made acidic by addition of hydrochloric acid. The mixture was heated at 70°-80° C. for 3 hours and the tetrahydrofuran was distilled off. After cooling, the mixture was extracted with ether and the ether phase was washed with water, dried over magnesium sulfate and concentrated. The residue was empasted with isopropyl ether, vacuum filtered and dried. The residue was crystallized from methanol, and dissolved in methanol and treated with activated carbon, concentrated and allowed to crystallize to obtain 10.3 g of 3-p-chlorobenzoyl-2-methyl-benzoic acid melting at 206° C. A second crop of 4.3 g of product was obtained by crystallization of the mother liquors.

1. customto rise to room temperature
2. temperaturecooled to -60° C.
3. customto return to room temperature
4. waitremain there overnight
5. temperatureThe mixture was heated at 70°-80° C. for 3 hours
6. distillationthe tetrahydrofuran was distilled off
7. temperatureAfter cooling
8. extractionthe mixture was extracted with ether
9. washthe ether phase was washed with water
10. dry with materialdried over magnesium sulfate
11. concentrationconcentrated
12. filtrationfiltered
13. customdried
14. customThe residue was crystallized from methanol
15. dissolutiondissolved in methanol
16. additiontreated with activated carbon
17. concentrationconcentrated
18. customto crystallize