The structural features of a molecule are determined by the covalent bonds within the molecule. Modification of the structure requires the breaking and creation of covalent bonds. Similarly, the intrinsic reactivity of a molecule arises from the covalently bonded functional groups and active sites on a molecule. Again, changing the properties requires modifications of the covalent bonds. Even i...

In the title compound, C(11)H(14)N(2)O(5)S, the amide O atom acts as a hydrogen-bond acceptor from a carboxyl-ate O atom and a secondary amino N atom. In addition, one of the sulfonyl O atoms and the carbonyl O atom of the carboxyl group also form hydrogen bonds with the primary amido N atom. These intermolecular hydrogen-bonding inter-actions give rise to a layer structure, with the layers par...

Molecular self-organization due to intermolecular hydrogen bonds is one of the most important phenomena which determine the structure and properties of numerous liquids. The entities formed can be composed of so many molecules, that the term “supramolecular polymers” is often used for describing the chains of molecules of low molecular weight linked by reversible, non-covalent interactions, suc...

Cyclooligomerization of 2,6-dichloropyrazine 4 and benzyl 2,3-dihydroxybenzoate 5 under microwave irradiation resulted in a racemic pair of ester functionalized ortho-linked oxacalix[2]benzene[2]pyrazine 6, which was further transformed to the corresponding racemic carboxylic acid functionalized ortho-linked oxacalix[2]benzene[2]pyrazine 3. Both enantiomers of 3 adopt 1,3-alternate conformation...

The serine phosphoric acid P-methylester (SPM) and the ethanol-amine phosphoric acid P-methylester (EPM) were synthesized as water soluble models for the functional groups of the corresponding phospholipids. Investigations were made of the aqueous solutions of these molecules as a function of deprotonation and proto nation. An intramolecular, easily polarisable hydrogen bond occurs in the zwitt...

The structural, vibrational, and energetic properties of adducts of alkanes and strong cationic proton donors were studied with composite ab initio calculations. Hydrogen bonding in D-H(+)...H-alkyl adducts contributes to a significant degree to the interactions between the two components, which is substantiated by NBO and AIM results. The hydrogen bonds manifest themselves in the same manner a...

In the crystal structure of the title compound, C(14)H(15)NO(2)S, the N-H bond is trans to one of the S=O double bonds, similar to what is observed in N-(2-methyl-phen-yl)benzene-sulfonamide and other aryl sulfonamides. The two aromatic rings enclose a dihedral angle of 44.9 (1)°. The mol-ecules are connected by inter-molecular N-H⋯O hydrogen bonds into chains running along the a axis. An inter...

In the title compound, C4H9Cl3N3O2P or CCl3C(O)NHP(O)(NHCH3)2, the P atom has a strongly distorted tetra-hedral geometry due to the formation of intermolecular strong hydrogen bonds involving the N atoms. In the crystal, N-H⋯O=P and N-H⋯O=C hydrogen bonds connect the mol-ecules into a two-dimensional array parallel to (100). An intra-molecular P⋯O contact [P⋯O = 2.975 (3) Å] is observed. The CC...

We have prepared some 3d-4f cyanide-bridged Ln(DMF)4(H2O)3Fe(CN)6•H2O complexes (Ln = Ce, Sm, Nd, and Gd; DMF = N,N-dimethylformamide) by substituting isotopes to H-substituted H2O and DMF and O-substituted H2O (and normal Hand O-H2O or H-DMF). We examined their crystal structures exhibiting negative thermal expansion and compared in view of hydrogen bonds and lanthanide contraction. Magnetic p...

The title compound, C(13)H(12)N(4)O, crystallizes with two independent mol-ecules in the asymmetric unit. The compound crystallizes as the ZE isomer, where Z and E refer to the configuration around the C=N and N-C bonds, respectively, with an N-H⋯N(py) (py is pyridine) intra-molecular hydrogen bond. The dihedral angles between the least-squares planes through the semicarbazone group and the pyr...