7-(Benzyloxy)-4-hydroxy-2H-1-benzopyran-2-one → 4,7-Dihydroxycoumarin

Beteiligte Stoffe

Reaktionsschritte

A 300 cc autoclave was charged with 7-benzyloxy-4-hydroxycoumarin (3 g, 3.7 mmol), prepared in accordance with Example 5, 5% Pd on carbon (0.18 g) and 85 mL of methanol and the autoclave was purged with N2. The autoclave was pressurized with H2 to a pressure of about 100 psi and maintained at that pressure. The exothermic reaction was carried out at ~50° C. for ~2hrs. After the completion of hydrogenolysis, the reactor was flushed with N2 and the contents were transferred into a beaker using a long pipet. The mixture containing Pd/C was dried over MgSO4 and filtered through a frit. The filtrate was evaporated to dryness and finally dried overnight at 45° C. The purity of the material as determined by LC was 95%; yield ~90%. The product was characterized by NMR.

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