The invention belongs to the field of medicinal synthesis, and particularly relates to a method for preparing
hydroxytyrosol, which comprises the following steps of: (1) protecting free hydroxyl groups at 3 and 4 positions, on 3,4-dihydroxy
benzaldehyde with benzyl, namely, reacting the 3,4-dihydroxy
benzaldehyde with
benzyl bromide to prepare 3,4-dibenzyloxybenzaldehyde; (2) reacting N-
methylaniline acetonitrile with the 3,4-dibenzyloxybenzaldehyde to prepare 3-(3,4-dibenzyloxyphenyl)-2-(methylphenylamino)
acrylonitrile, and hydrolyzing the 3-(3,4-dibenzyloxyphenyl)-2-(methylphenylamino)
acrylonitrile under acidic condition to prepare a 3,4-dibenzylosyphenylacetic acid; (3) reducing a carboxyl group of the 3,4-dibenzylosyphenylacetic acid with
lithium borohydride,
lithium aluminum hydride or
sodium borohydride to prepare 3,4-dibenzyloxyphenethyl
alcohol; and (4) catalyzing the 3,4-dibenzyloxyphenethyl
alcohol with a catalyst
palladium / carbon to prepare the
hydroxytyrosol. The reagents used in the method are easily obtainable and low in cost,
reaction conditions are mild, and the final overall yield of the whole reaction reaches 50 to 60 percent.