Grignard reagent (II) prepared from 1,4-dibromobenzene (I) was condensed with biphenylaldehyde (III) to afford alcohol (IV), which was oxidized to ketone (V) under Swern conditions with oxalyl chloride and DMSO at low temperature. Then, allylic bromination with N-bromosuccinimide (NBS) in the presence of azobisisobutyronitrile (AIBN) gave (VI). Finally, N-allyl-N-methylamine (VII) was alkylated with bromide (VI) to provide the tertiary amine.