STRUCTURE OF 4-[(2-BENZOYL-1-METHYL)VINYLENEIMINO]BUTYRIC ACID

C 14HlTNO3, M r : 247.29, monoclinic, P21/n, a=12.109(5), b=10.907(3), c=10.846(3) A, beta = 113.06(2) ° , V= 1318.0 (8) A 3, Z=4, Dx = 1.246, D m = 1.25 g cm -3 (by flotation), 2(Cu Ks) = 1.54178 A, g = 6.781 cm -m, F(000) = 528, T= 298 K, R = 0.0525 for 1425 observed reflections. The enaminone system in the title compound is very nearly planar and has a cis-s-cis conformation. The resulting six-membered ring involves a hydrogen bond between the NH and the ketonic carbonyl. The conformation of the carboxypropyl fragment enables molecules related by a centre of symmetry to organize in dimeric structures characterized by hydrogen bonding between the two enaminone heteroatoms of one molecule and the carboxylic oxygens of the other.