反应详情

6.5 g of 4-(2,3-dihydro-2,2-dimethyl-5-benzofuranyloxy)aniline was dissolved in 30 ml of pyridine, and 3.8 g of N-methoxy-N-methylcarbamoyl chloride was gradually dropwise added thereto over a period of 30 minutes under cooling with ice. Stirring was continued for 1.5 hours, and then pyridine was distilled off under reduced pressure. The residual oily substance was dissolved in 100 ml of toluene, and washed sequentially with water, a dilute hydrochloric acid aqueous solution and a saturated sodium chloride aqueous solution. Then, toluene was distilled off. The residue was purified by silica gel column chromatography by using a solvent mixture of ethyl acetate/n-hexane=1/3 as the developer, to obtain 7.5 g of compound No. 19 as identified in Table 1.

1. temperatureover a period of 30 minutes under cooling with ice
2. distillationpyridine was distilled off under reduced pressure
3. dissolutionThe residual oily substance was dissolved in 100 ml of toluene
4. washwashed sequentially with water
5. distillationThen, toluene was distilled off
6. customThe residue was purified by silica gel column chromatography
7. additiona solvent mixture of ethyl acetate/n-hexane=1/3 as the developer