We report the elusive X-ray structure of the Dess-Martin periodinane (DMP), a hypervalent iodine reagent popular amongst synthetic chemists. In the solid state, the highly crystalline compound forms an intricate coordination polymer held together by intermolecular halogen and hydrogen bonds.

Three novel nitrogen-containing macrolides have been synthesized by esterification. All of them have been characterized by infrared (IR), elemental analysis, mass spectra (MS), and 1H NMR spectroscopy, and their crystal structures were determined by single-crystal X-ray diffraction. The preparation methods and the intermolecular associations based on C–H· · ·O hydrogen bonds and ππ stacking int...

In the approximately planar molecule of the title compound, C(11)H(8)N(4)O(4)S, the dihedral angle between the thio-phene and benzene rings is 5.73 (10)°. In the crystal structure, bifurcated inter/intra-molecular N-H⋯(O,O) hydrogen bonds are present. The intermolecular links lead to inversion dimers containing an R(2) (2)(12) graph-set motif.

In the title compound, C(13)H(12)ClNO, the dihedral angle between the two benzene ring planes is 68.71 (8)°. In the crystal, mol-ecules are linked by pairs of O-H⋯N hydrogen bonds into inversion dimers, which are further linked by intermolecular N-H⋯O interactions into a chain running parallel to the a axis.

In the title compound, C(15)H(12)O(3)·H(2)O, the two rings are oriented at a dihedral angle of 69.12 (3)°. In the crystal structure, intermolecular O-H⋯O hydrogen bonds link the mol-ecules into a three-dimensional framework.

In the title compound, C(23)H(24)N(4)OS, the piperidine and cyclo-hexane rings adopt twin chair conformations and the phenyl groups occupy equatorial positions. The dihedral angle between the two benzene rings is 10.25 (12)°. The crystal structure is stabilized by intermolecular N-H⋯O hydrogen bonds with the formation of centrosymmetric dimers.

A low volume shrinking vinylcyclopropane (VCP) monomer, showing both a high reactivity and a low viscosity, was obtained by applying a sterically hindered and isomeric spacer element, incorporating intermolecular amide hydrogen bonds. The resulting properties locate this VCP system in a pronounced range that so far no other efficient and radical polymerizable resin could enter.

In the title compound, C(17)H(13)N(3)OS, the dihedral angle between the ring systems is 2.22 (5)°. The N-H grouping participates in both intra- and intermolecular N-H⋯O hydrogen bonds, the latter leading to dimers related by a twofold rotation axis.

In the title compound, C(10)H(12)O(5), the dihedral angle between the benzene ring is almost coplanar with the attached C(O)-O-C group [dihedral angle = 0.32 (15)°]. In the crystal, two intermolecular O-H⋯O hydrogen bonds make R(4) (4)(26) ring mofits.

We investigate the quantum dynamical nature of hydrogen bonding in 1,2-ethanediol and monohydrated 1,2-ethanediol using different levels of ab initio theory. Global full-dimensional potential energy surfaces were constructed from PW91/cc-pVDZ, B3LYP/cc-pVDZ, and MP2/cc-pVDZ ab initio data for gas-phase and monohydrated 1,2-ethanediol, using a modified Shepard interpolation scheme. Zero-point en...