Synthesis, spectroscopic characterizations and quantum chemical computational studies of (Z)-4-[(E)-(4-fluorophenyl)diazenyl]-6-[(3-hydroxypropylamino)methylene]-2-methoxycyclohexa-2,4-dienone.

In this study, the molecular structure and spectroscopic properties of the title compound were characterized by X-ray diffraction, FT-IR and UV-vis spectroscopies. These properties were also investigated using DFT method. The most convenient conformation of title compound was firstly determined.

(E)-2-Eth-oxy-6-[(4-ethoxy-phen-yl)imino-meth-yl]phenol.

In the asymmetric unit of the title compound, C(17)H(19)NO(3), there are three independent mol-ecules, which are align nearly parallel to each other and adopt the phenol-imine tautomeric form. In each mol-ecule, an intra-molecular O-H⋯N hydrogen bond results in the formation of an S(6) ring motif. The dihedral angles between the aromatic rings in the three independent mol-ecules are 13.

(E)-4-Meth-oxy-2-(p-tolyl-imino-meth-yl)phenol.

The mol-ecule of the title compound, C(15)H(15)NO(2), adopts the enol-imine tautomeric form and has a strong intra-molecular O-H⋯N hydrogen bond as a result. The mol-ecule is almost planar, with a maximum deviation of 0.1038 (15) Å for the meth-oxy C atom.

(E)-2-[(4-Fluoro-phen-yl)imino-meth-yl]-5-methoxy-phenol.

In the mol-ecule of the title compound, C(14)H(12)FNO(2), the aromatic rings are oriented at a dihedral angle of 48.17 (1)°. An intra-molecular O-H⋯N hydrogen bond results in the formation of a six-membered ring.

(E)-5-Meth-oxy-2-(o-tolyl-imino-meth-yl)phenol.

In the title compound, C(15)H(15)NO(2), the phenol group make dihedral angles of 2.4 (2) and 24.1 (9)° with the imine linkage (-C=N-) and the phenyl group, respectively, and the mol-ecule adopts the enol-imine tautomeric form, so the mol-ecular structure is stabilized by a strong intra-molecular O-H⋯N hydrogen bond.

(Z)-6-[(5-Chloro-2-hydroxy-anilino)-methyl-ene]-4-methoxy-cyclo-hexa-2,4-dienone 0.25-hydrate.

The title compound, C(14)H(12)ClNO(3)·0.25H(2)O, exists in the keto-amine form, and the aromatic rings are oriented at a dihedral angle of 7.24 (7)°.

(E)-4-Meth-oxy-2-(o-tolyl-imino-meth-yl)phenol.

In the mol-ecule of the title compound, C(15)H(15)NO(2), the aromatic rings are oriented at a dihedral angle of 15.46 (6)°. An intra-molecular O-H⋯N hydrogen bond results in the formation of a nearly planar six-membered ring [maximum deviation of 0.

(E)-2-[(4-Ethoxy-phen-yl)imino-meth-yl]-4-methoxy-phenol.

In the mol-ecule of the title compound, C(16)H(17)NO(3), the aromatic rings are oriented at a dihedral angle of 29.25 (8)°. An intra-molecular O-H⋯N hydrogen bond results in the formation of a nearly planar [maximum deviation 0.

(Z)-6-[(5-Chloro-2-hydroxy-phenyl)-aminomethyl-ene]-2-ethoxy-cyclo-hexa-2,4-dienone.

The title compound, C(15)H(14)ClNO(3), exists as the keto-amine form in the crystal and two intra-molecular N-H⋯O hydrogen bonds are observed. The aromatic rings are oriented at a dihedral angle of 5.85 (8)°.

X-ray and computational structural study of (E)-2-(4-chloro-phenyl-imino-meth-yl)-4-methoxy-phenol.

In the mol-ecule of the title compound, C(14)H(12)ClNO(2), the two aromatic rings are oriented at a dihedral angle of 5.92 (7)°. An intra-molecular O-H⋯N hydrogen bond results in the formation of a nearly planar six-membered ring, which is oriented at dihedral angles of 1.

X-ray crystal and computational structural study of (E)-2-[(2-chloro-phenyl)-iminometh-yl]-4-methoxy-phenol.

In the mol-ecule of the title compound, C(14)H(12)ClNO, the two aromatic rings are oriented at a dihedral angle of 12.28 (7)°. An intra-molecular O-H⋯N hydrogen bond results in the formation of a nearly planar six-membered ring, which is oriented with respect to the aromatic rings at dihedral angles of 0.

1,4-Bis[2-(1,3-benzothia-zol-2-yl)phen-oxy]butane.

The mol-ecule of the title compound, C(30)H(24)N(2)O(2)S(2), adopts a transoid conformation consistent with the inversion centre located at the mid-point of the central C-C single bond, resulting in one half mol-ecule in the asymmetric unit. The dihedral angle between the coplanar benzothia-zole ring system and the benzene ring is 11.06 (7)°.

Three (E)-2-[(bromophenyl)iminomethyl]-4-methoxyphenols.

The title compounds, (E)-2-[(2-bromophenyl)iminomethyl]-4-methoxyphenol, C(14)H(12)BrNO(2), (I), (E)-2-[(3-bromophenyl)iminomethyl]-4-methoxyphenol, C(14)H(12)BrNO(2), (II), and (E)-2-[(4-bromophenyl)iminomethyl]-4-methoxyphenol, C(14)H(12)BrNO(2), (III), adopt the phenol-imine tautomeric form. In all three structures, there are strong intramolecular O-H..