反应详情

To a large hydrogenation vessel were added ethyl 7-hydroxychromone-2-carboxylate (=ethyl 7-hydroxy-4-oxo-4H-chromene-2-carboxylate) (675.4 g, 2.88 mol), EtOH 4 liters, conc. hydrochloric acid 40 ml. The resulting suspension was combined with 5% Pd/C 68 g, and subjected to hydrogenation condition (H2, 40 psi, rt) overnight. The reaction mixture was filtered through a pad of celite to remove the catalyst. The filtrate was concentrated to give thick oily material, which solidified upon standing. Tan solid 630.1 g (98%).

1. customsubjected to hydrogenation condition (H2, 40 psi, rt) overnight
2. filtrationThe reaction mixture was filtered through a pad of celite
3. customto remove the catalyst
4. concentrationThe filtrate was concentrated
5. customto give thick oily material, which