Dichlorophenylpiperazine (III) was prepared from aniline (I) by dehydrative cyclization with diethanolamine (II) in the presence of P2O5 and Et3N-HCl at 200 C. Alkylation of piperazine (III) with N-(4-bromobutyl) phthalimide (IV) gave (V), and subsequent hydrazinolysis of the phthalimide provided the (4-aminobutyl)piperazine (VI). Finally, condensation of (VI) with fluorene-2-carboxylic acid (VII) yielded the target amide.

Dichlorophenylpiperazine (III) was prepared from aniline (I) by dehydrative cyclization with diethanolamine (II) in the presence of P2O5 and Et3N-HCl at 200 C. Alkylation of piperazine (III) with N-(4-bromobutyl) phthalimide (IV) gave (V), and subsequent hydrazinolysis of the phthalimide provided the (4-aminobutyl)piperazine (VI). Finally, condensation of (VI) with biphenylene-2-carboxylic acid (VII) yielded the target amide.