(Z)-methyl 3-(4-ethoxyanilino)but-2-enoate

The title compound, C13H17NO3, was synthesized from methyl 3-oxobutanoate and 4-ethoxybenzenamine using a catalytic amount of InBr3 under solvent-free conditions. The 3-amino-but-2- enoic acid methyl ester group is planar and forms a dihedral angle of 83.4 (1)degrees with the benzene ring. The ethoxy group is slightly twisted away from the benzene ring [dihedral angle = 13.8 (1)degrees]. An intramolecular N-H center dot center dot center dot O hydrogen bond generating an S( 6) ring is observed. Molecules are linked into a chain along the b axis by intermolecular C-H center dot center dot center dot O hydrogen bonding.