The reaction of 1-(4-methoxyphenyl)-2-phenylethan-1-one (I) with ethyl bromide (A) gave (II) in nearly quantitative yield. Demethoxylation of (II) with pyridine hydrochloride gave (III) in about 70% yield. Treatment of (III) with dimethylaminoethyl chloride (B) gave (IV) in more than 60% yield. Reaction of (IV) with 3'-(2-tetrahydropyranyloxy)phenylmagnesium bromide (C) gave (V) in about 60% yield. Refluxing a solution of (V) in ethanolic hydrochloric acid gave the stereoisomeric E- and Z-mixture (VIa, VIb) of the hydrochloric salt. Fractional crystallization of the mixture in methanol/ether yielded the pure hydrochloric salt of the E-isomer in 48% yield. Conversion of the hydrochloric salt into the free base and treatment of the latter with citric acid yielded the appropriate K-21060E citrate.

The reaction of 1-(4-methoxyphenyl)-2-phenylethan-1-one (I) with ethyl bromide (A) gave (II) in nearly quantitative yield. Demethoxylation of (II) with pyridine hydrochloride gave (III) in about 70% yield. Treatment of (III) with dimethylaminoethyl chloride (B) gave (IV) in more than 60% yield. Reaction of (IV) with 3'-(2-tetrahydropyranyloxy)phenylmagnesium bromide (C) gave (V) in about 60% yield. Refluxing a solution of (V) in ethanolic hydrochloric acid gave the stereoisomeric E- and Z-mixture (VIa, VIb) of the hydrochloric salt. Fractional crystallization of the mixture in methanol/ether yielded the pure hydrochloric salt of the E-isomer in 48% yield. Conversion of the hydrochloric salt into the free base and treatment of the latter with citric acid yielded the appropriate K-21060E citrate.