The alkylation of 4-(4-methoxyphenyl)piperidine (I) with 4-phenylbutyl tosylate (II) provided the tertiary amine (III). The methyl ether group of (III) was then cleaved using BBr3 to furnish the title phenol.
In an alternative procedure, lithiation of 4-(benzyloxy)-1-bromobenzene (IV), followed by addition of 1-benzyl-4-piperidone (V), gave piperidinol (VI). Subsequent treatment of (VI) with HCl produced dehydration of the tertiary alcohol and benzyl ether cleavage to give (VII). Double bond reduction and hydrogenolysis of the N-benzyl group of (VII) with H2 over Pd/C gave 4-(4-hydroxyphenyl)piperidine (VIII). This was finally alkylated with tosylate (II) to yield the title compound.