HPLC Separation of Aminobiphenyls

Aminobiphenyls consist of isomers that differ only in the location of a primary amine group on an aromatic ring. 2-, 3-, and 4-aminobiphenyl are separated on a Primesep D with good peak shape and a short retention time by a mixture of reversed-phase and ion-exclusion interactions. Peak order can be reversed for 2- and 3-aminobiphenyls by using ammonium formate buffer without pH adjustment. The HPLC separations use a mobile phase of water, acetonitrile (MeCN, ACN), ammonium formate buffer or acetic acid (HOAc) with UV detection at 250 nm.