Synthesis of some new anils: part 1. Reaction of 2-hydroxy-benzaldehyde and 2-hydroxynaphthaldehyde with 2-aminopyridene and 2-aminopyrazine.
New Schiff bases derived from 2-aminopyridene and 2-aminopyrazine have been synthesized. The UV-Visible spectra of the compounds have been investigated in acetonitrile and toluene. The compounds were in tautomeric equilibrium (enol-imine O- H...N, keto-amine O...H-N forms) in polar and nonpolar solvents. For some derivatives the keto-amine form was observed in both toluene and acetonitrile. 1H-NMR and IR results showed that all Schiff bases studied favor the enol-imine form over the keto form in a weakly polar solvent such as deuterochloroform.
Methyl 2-(2-hydroxybenzylideneamino)-4,5,6,7-tetrahydro-1-benzothiophene-3-carboxylate
In the title compound, C17H17NO3S, the cyclohexene ring is essentially planar, with a maximum deviation of 0.006 (1) Å. The cyclohexene ring adopts a half-chair conformation. The dihedral angle between the thiophene and benzene rings is 29.7 (1)°. The molecular structure exhibits intramolecular O—H⋯O, O—H⋯N and C—H⋯S hydrogen bonds, which generate one S(5) and two S(6) motifs. There is also a C—H⋯π interaction between the cyclohexene ring system and the π-system of the benzene ring.
Crystal and molecular structure of an anchored catechol ligand: 2,3-dihydroxy benzenemethanimine α-(2-hydroxymethyl)phenyl
The structure of the new tetranucleating ligand 2,3,-dihydroxy benzenemethanimine α-(2-hydroxymethyl)phenyl has been determined by X-ray diffraction techniques. C14H13NO3 is monoclinic, space groupP21/a, with cell dimensionsa=10.382(2),b=19.147(1),c=12.799(1) Å,β=113.08(1)°,V=2340.6(3) Å3,Z=8,M=243.04,Do=1.36,Dx=1.38 mg/m3,F(000)=1024,T=293 K,R=0.041 for 2640 observed reflections. There are two molecules in the asymmetric unit and both have a similar geometry. The molecules are parallel to each other, the distance between them being 3.7 Å and the dihedral angle between mean planes 7.8°. There is a pseudocenter between molecule A and (1−x, 1−y, 1−z) of molecule B. The structure is stabilized by intramolecular O-H⋯N and intermolecular O-H⋯O as well as by C-H⋯O hydrogen bonds.