反应详情

Using 5.05 g of 2,3-dimethoxy-5-methyl-1,4-dihydroxybenzene, 3.80 g of benzoyl chloride and 100 ml of pyridine, reaction and workup carried out as in the Reference Example gave 5.57 g of 4-benzoyloxy-2,3-dimethoxy-5-methylphenol, m.p. 109-111° C. Then, this 5.57 g was dissolved in 50 ml of DMF and added dropwise under an argon gas flow to a suspension of 0.84 g of sodium hydride in 50 ml of DMF. After the addition, stirring was continued for 30 minutes, and 2.6 ml of benzyl bromide was added dropwise and stirring continued for 2 hours at room temperature. The reaction mixture was poured into ice water, extracted with ethyl ether, washed with water, the solvent evaporated under reduced pressure, and thus obtained residue dissolved in 100 ml of methyl alcohol, and to this was added dropwise 5.10 g of sodium methylate (28% methyl alcohol solution) under ice-cooling and stirred for 12 hours at room temperature. Evaporation of the solvent under reduced pressure, neutralization with 2N HCl, extraction with ethyl ether and then evaporation of the solvent under reduced pressure gave 3.69 g of yellow oil.