Reaction of 4-methylpropiophenone (I) with nitrating acid yields 4-methyl-3-nitropropiophenone (II), which is reduced to the corresponding aniline derivative (III) by means of catalytic hydrogenation. Diazotation of (III) followed by heating the aqueous solution of the intermediate diazonium salt affords 3 hydroxy-4-methylpropiophenone (IV), which is protected by etherification with benzyl chloride giv ing 3-benzyloxy-4-methylpropiophenone (V). Bromination of (V) and subsequent reaction of the resulting a bromoketone (VI) with N-benzyl-N-(3-phenylpropyl)amine yields the tertiary amine (VII), which is finally debenzylated and reduced by catalytic hydrogenation over Pd/C.

Reaction of 4-methylpropiophenone (I) with nitrating acid yields 4-methyl-3-nitropropiophenone (II), which is reduced to the corresponding aniline derivative (III) by means of catalytic hydrogenation. Diazotation of (III) followed by heating the aqueous solution of the intermediate diazonium salt affords 3 hydroxy-4-methylpropiophenone (IV), which is protected by etherification with benzyl chloride giv ing 3-benzyloxy-4-methylpropiophenone (V). Bromination of (V) and subsequent reaction of the resulting a bromoketone (VI) with N-benzyl-N-(3-phenylpropyl)amine yields the tertiary amine (VII), which is finally debenzylated and reduced by catalytic hydrogenation over Pd/C.