Synthesis, Characterization, Crystal and Molecular Structure Analysis of 2,6-Dimethyl-3-acetyl-5-carbomethoxy-4-(3-nitrophenyl)-1,4-dihydropyridine

A novel unsymmetrical dihydropyridine, possessing carboxymethyl and carbomethoxy groups at C(3) and C(5), respectively, has been produced using a modified Hantzsch synthesis, under solvent free conditions, in a domestic microwave oven. The product obtained was characterized by spectroscopic techniques and finally confirmed by X-ray diffraction studies. The title compound C17H18N2O5 crystallizes in the monoclinic system in the space group P2(1)/c with cell parameters a = 12.860(2) angstrom, b = 7.4950(6) angstrom, c = 16.734(3) angstrom, beta = 94.436(3)degrees, Z = 4 and V = 1608.1(4) angstrom(3). The 1,4-dihydropyridine ring in the structure is in a flattened boat conformation. The molecule possesses a chiral center at C4. The 3-nitrophenyl ring is nearly orthogonal to the 1,4-dihydropyridine ring. The carbonyl groups at C3 and C5 are oriented in -antiperiplanar and +synperiplanar conformations, respectively. The structure exhibits both inter and intramolecular hydrogen bonds of the type N-H center dot center dot center dot O and C-H center dot center dot center dot O.