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A novel compound, 5,5'-(1,4-phenylenedimethylylidene)bis(1,3-diethyl-2-thioxodihydropyrimidine-4,6(1H,5H)-dione) (3) has been synthesized by condensation of 1,3-diethyl-2-thiobarbituric acid and terephthalaldehyde in anhydrous ethanol in the presence of pyridine. The structure of this compound was established by elemental analysis, IR, 1H-NMR, 13C-NMR and EI-MS spectral analysis.
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
In the title mol-ecule, C(23)H(16)N(2)O(2), the two exocyclic C=C bonds bearing the tolyl groups have an E configuration and the beznene rings are oriented at 22.1 (1) and 24.8 (1)° with respect to the mean plane of the atoms of the furan ring.
In the title co-crystal, C(6)H(6)N(2)O(2.)C(10)H(12)O(4), the two components are held together by an N-H⋯O(aldehyde) hydrogen bond. Adjacent co-crystals are linked by weaker N-H⋯O(nitro) hydrogen bonds, forming a linear chain. The two aromatic rings of the components are aligned at 75.2 (1)°. The crystal studied was a non-merohedral twin with a 24% minor component.
Abstract An interesting flourophore, 4‐(2,5‐dimethoxyphenylmethelene)‐2‐phenyl‐5‐oxazolone (DMPO) was synthesized by mixing an equivalent molar quantity of hippuric acid and 2,5‐dimethoxybenzaldehyde in acetic anhydride in the presence of anhydrous sodium acetate. The absorption and fluorescence characteristics of 4‐(2,5‐dimethoxy‐phenylmethelene)‐2‐phenyl‐5‐oxazolone (DMPO) were investigated in different solvents. DMPO dye exhibits red shift in both absorption and emission spectra as solvent polarity increases, indicating change in the dipole moment of molecules upon excitation due to an intramolecular charge transfer interaction. The fluorescence quantum yield depends strongly on the properties of the solvents, which was attributed to positive and negative solvatokinetic effects. A crystalline solid of DMPO gave strong excimer like emission at 630 nm due to the excitation of molecular aggregates. This is expected from the idealized crystal structure of the dye that belongs to the B‐type class of Steven's Classification. DMPO displayed fluorescence quenching by triethylamine via nonemissive exciplex formation.
Abstract Title compounds are synthesized by reaction of pyrazoles (I) with isocyanates (II) or isothiocyanates (IV), resp., followed by intermolecular cyclization reactions.