Isopropanol → 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

Participants

Reaction Steps

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.

Provenance & Evidence