反应详情

A solution of 6-nitro-2,2,3-trimethyl-3,4-dihydro-3,4-epoxy-2H-1-benzopyran (9.93 g, 0.0422 mol), 2(1H)-pyridinone (8.04 g, 0.0845 mol) and Triton B (40% in ethanol, 2.5 ml) in dioxan (100 ml) was heated at reflux for twenty hours. Water and ethyl acetate were added to the cooled solution, the organic phase separated and the solvent removed under reduced pressure. The residue was washed with diethyl ether and pentane, to give 3.53 g of 6-nitro-2,2,3-trimethyl-4-(2-oxo-1,2-dihydropyridin-1-yl)-3,4-dihydro-3-hydroxy-2H-1-benzopyran, m.p. 214° C.

1. temperatureat reflux for twenty hours
2. customthe organic phase separated
3. customthe solvent removed under reduced pressure
4. washThe residue was washed with diethyl ether and pentane