bonds [either N–H···O (keto-amine tautomer) or N···H–O (phenol-imine tautomer)] can exist. It is claimed that the hydrogen-bond type depends neither on the stereochemistry of the molecule nor on the sort of substituent bonded to the N imino atom, but on the kind of aldehyde used.1 In the solid state, it is also claimed that only an intramolecular N–H···O type hydrogen bond is present in naphtha...

The association of substituted benzoates and naphthyridine dianions was used to study the complexation of dibutyltriuret. The title molecule is the simplest molecule able to form two intramolecular hydrogen bonds. The naphthyridine salt was used to break two intramolecular hydrogen bonds at a time while with the use of substituted benzoates the systematic approach to study association was achie...

The mol-ecule of the title compound, C(15)H(14)N(2)O(4), displays a trans configuration with respect to the hydrazide C=N bond. The dihedral angle between the two benzene rings is 15.0 (2)°. In the crystal structure, mol-ecules are linked through inter-molecular O-H⋯N and O-H⋯O hydrogen bonds, forming layers parallel to the ab plane; an intramolecular N-H⋯O hydrogen bond is also present.

In the title racemic compound, C(26)H(32)N(2)O(3), an intra-molecular O-H⋯N hydrogen bond is formed between the phenolic OH group and the tertiary amine N atom. Another O-H⋯N hydrogen bond that is formed between the OH group and the pyridine N atom links the mol-ecules into a polymeric chain extending along the a axis. The structure is further stabilized by intramolecular and intermolecular C-H...

The molecule of the title compound, C(15)H(16)N(2)O, is non-planar with a dihedral angle of 16.0 (1)° between the pyrrole and benzene rings. The ketone double-bond displays an s-cis conformation with an O=C-C=C torsion angle of 7.9 (3) and an intramolecular C-H⋯O hydrogen bond. In the crystal structure, adjacent mol-ecules are paired through N-H⋯O hydrogen bonds into centrosymmetric dimers.

This is a review of investigations on iodo-benzoic acid, iodohippuric acid, and iodophenol derivatives by NQR, N M R , and emission Mössbauer spectroscopy. The influence of intermolecular, intramolecular, and bifurcated O H • I and O H • O bonds on the properties of iodine-carbon bonds is demonstrated. Ionized and non-ionized forms of tyrosine differ by the probability of H-bond formation. The ...

The mol-ecule of the title compound, C(14)H(10)Cl(2)N(2)O(2), displays a trans configuration with respect to the C=N double bond and has an intramolecular O-H⋯N hydrogen bond. The dihedral angle between the two benzene rings is 1.4 (2)°. In the crystal structure, mol-ecules are linked through inter-molecular N-H⋯O hydrogen bonds, forming chains running along the a direction.

The title compound, C(10)H(12)N(2)O(4), adopts a trans configuration with respect to the C=N bond. The hydrazinecarboxyl-ate group is twisted from the benzene ring by 6.62 (5)° and an intramolecular O-H⋯O hydrogen bond occurs. In the crystal structure, mol-ecules are linked into a two-dimensional network parallel to (100) by O-H⋯O, N-H⋯O and C-H⋯O hydrogen bonds. In addition, weak C-H⋯π inter-a...

In the title compound, [CoCl2(H2O)4]·2C4H8SO2, the Co(II) cation is located on the twofold rotation axis and is coordinated by four water mol-ecules and two adjacent chloride ligands in a slightly distorted octa-hedral coordination environment. The cisoid angles are in the range 83.27 (5)-99.66 (2)°. The three transoid angles deviate significantly from the ideal linear angle. The crystal packin...