反应详情

5.06 g of benzyl 6-(6-cyano-2,2-dimethyl-2H-1-benzopyran-4-yl)-3-pyridinecarboxylate were heated at 100° C. with 7.8 ml of tributylamine, 244 mg of 10% palladium-on-charcoal and 0.9 ml of formic acid. After 12 hours a further 7.8 ml of tributylamine and 10 ml of formic acid were added. After 24 hours a further 2 ml of tributylamine and 3 ml formic acid were added. After 26 hours a further 170 mg of 10% palladium-on-charcoal, 2 ml tributylamine and 3 ml of formic acid were added. After 28 hours the mixture was evaporated and filtered. The filtrate was evaporated and the residue obtained was chromatographed on silica gel using ethyl acetate/petroleum ether (1:2) and ethyl acetate for the elution. There were obtained 1.4 g of 6-(6-cyano-2,2-dimethyl-2H-1-benzopyran-4-yl)-3-pyridinecarboxylic acid which was used without further purification.

1. customAfter 28 hours the mixture was evaporated
2. filtrationfiltered
3. customThe filtrate was evaporated
4. customthe residue obtained
5. customwas chromatographed on silica gel
6. washfor the elution