Methanol → HCID 14985932, compound

Participants

Reaction Steps

With protection from moisture, 0.42 g (10.6 mmol) of sodium hydride (60% dispersion) is slowly added at 60° C., with stirring, to 3.10 g (10.6 mmol) of methyl 5,8-dimethoxy-7-hydroxy-2-methyl-4-oxo-4H-1-benzopyran-6-carboxylate dissolved in 50 ml of anhydrous dimethylformamide. After a contact period of 11/2 hours, 1.30 ml (21.2 mmol) of iodomethane are added to the reaction mixture and stirring is continued for 2 hours. After decomposition of the excess sodium hydride by the addition of methanol, the reaction mixture, diluted with diethyl ether, is filtered. Evaporation of the filtrate results in an orange oil which is taken up in water and extracted 3 times with 50 ml of diethyl ether each time. The combined organic phases are washed with a saturated solution of NaCl and dried over Na2SO4 and then the solvents are removed. Chromatography of the powdery residue on a silica gel column (70-230 mesh; eluant: CH2Cl2 /CH 3 OH: 99/1) yields 2.5 g of orange crystals.

Provenance & Evidence