0000000000222716
AUTHOR
Wojciech Zielinski
3,5-diphenyl-1,2,4-triazin-6(1H)-one: synthesis, and X-ray and DFT-calculated structures.
The title compound, C15H11N3O, (I), was obtained by the air oxidation of 3,5-diphenyl-4,5-dihydro-1,2,4-triazin-6(1H)-one. In the crystal structure, (I) forms centrosymmetric hydrogen-bonded dimers through pairs of N—H...N hydrogen bonds. The molecular structure of (I) deviates somewhat from planarity in the crystalline state, whereas a density functional theory (DFT) study predicts a completely planar conformation (Cspoint-group symmetry) for the isolated molecule. The solid-state conformation of (I) is stabilized by intramolecular hydrogen bonds,viz.one C—H...O interaction, which forms a six-membered ring, and three C—H...N interactions that each form five-membered rings. To estimate the …
The reaction of optically active α-aminocarboxylic acid hydrazides with triethyl orthoesters
New derivatives of 2-(1-amino-1-phenylmethyl)-1,3,4-oxadiazole and 1,2,4-triazin-6-one were synthesised in the reactions of optically active α-aminocarboxylic acid hydrazides and triethyl orthoesters in xylene. The electronic and steric effects of substituents at the α position influencing the formation of five- or six-membered products are discussed.
1-[(1-ethoxypropylidene)amino]-2-ethyl-4-(4-hydroxybenzyl)imidazol-5(4H)-one.
The racemic title compound, C17H23N3O3, isolated from the reaction of L-(−)-tyrosine hydrazide with triethyl orthopropionate in the presence of a catalytic quantity ofp-toluenesulfonic acid (p-TsOH), crystallizes withZ′ = 1 in a centrosymmetric monoclinic unit cell. The molecule contains two planar fragments,viz.the benzene and imidazole rings, linked by two C—C single bonds. The dihedral angle between the two planes is 59.54 (5)° and the molecule adopts a synclinal conformation. The HOMA (harmonic oscillator model of aromaticity) index, calculated for the benzene ring, demonstrates no substantial interaction between the two π-electron delocalization regions in the molecule. In the crystal …