4-Hydroxybenzoic Acid → Tert-butyl 4-{4-[(4-hydroxybenzoyl)amino]phenyl}piperazine-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

To a solution of tert-butyl 4-(4-aminophenyl)piperazine-1-carboxylate (1 eq), 4-hydroxybenzoic acid (1.1 eq), N-methylmorpholine (3 eq) in dry DMF (0.16 M), was added PyBop (1.5 eq). The reaction mixture was heated at 60° C. with stirring for 60 h. At this time the reaction was allowed to cool to RT partitioned between EtOAc and 1N aqueous HCl. The aqueous fraction was extracted with EtOAc and the combined organics washed with saturated aqueous Na2CO3, brine, before being dried over Na2SO4, filtered and evaporated in vacuo. Purification was by flash chromatography on silica gel (4:6) EtOAc/PE) to afford the title compound (24%).

Provenance & Evidence