2H-pyran-3,5(4H,6H)-dione → 4-(3-bromo-4-methylphenyl)-1-methyl-4,9-dihydro-1H-isoxazolo [3,4-b]pyrano[4,3-e]pyridine-3,5(6H,8H)-dione

Participants

Reaction Conditions

Reaction Steps

The product from Example 45A (0.11 g, 1 mmol), 4-methyl-3-bromobenzaldehyde (0.2 g, 1 mmol), prepared as described in (Pearson et al., J.Org. Chem.(1958),23,1412-1416) and 2H-pyran-3,5(4H,6H)-dione (0.11 g, 1 mmol) in ethyl alcohol (2 mL) were heated at 80° C. for 2 days in a sealed tube. The reaction mixture was allowed to cool to ambient temperature and was evaporated under reduced pressure. The residue was chromatographed eluting with 19:0.5:0.5 ethylacetate:formic acid:water to provide the title compound (0.07 g).

Provenance & Evidence