反应详情

A mixture of 6-cyano-3,4-dihydro-2,2-dimethyl-trans-3-hydroxy-4-amino-2H-1-benzopyran (4.7 g), 4-chloro-3-methoxy-2-E-butenoic acid, methyl ester (3.55 g), potassium carbonate (5.95 g) and sodium iodide (3.2 g) was refluxed for 3 hours in isopropanol. After cooling the mixture was filtered and solvent removed from the filtrate under reduced pressure, to give 1.1 g of 6-cyano-3,4-dihydro-2,2-dimethyl-trans-3-hydroxy-4-(2-methoxy-3-carbonylmethoxy-2-E-propen-1-yl)amino-2H-1-benzopyran, a compound of formula (6). The compound was used in the next reaction (Example 3) with no further purification.

1. temperatureAfter cooling the mixture
2. filtrationwas filtered
3. customsolvent removed from the filtrate under reduced pressure