Halogen bonding in ligand-protein complexes is currently widely exploited, e.g. in drug design or supramolecular chemistry. But little attention has been directed to other effects that may result from replacement of a hydrogen by a strongly electronegative halogen. Analysis of almost 30000 hydrogen bonds between protein and ligand demonstrates that the length of a hydrogen bond depends on the t...

The dechlorination of chlorinated hydrocarbons has been examined in detail. The reaction is catalyzed by cytochrome P-450 and occurs optimally in the presence of oxygen although some dechlorination may occur under anaerobic conditions. Halothane has been shown to undergo an oxidative dechlorination and a reductive defluorination. Enzymatic attack of chlorinated olefins and hydrocarbons is not o...

The purpose of this study was to compare the shear bond strength of orthodontic metallic brackets photo-activated with two different light-curing sources at different exposure times: halogen light (XL 1500, 3M ESPE) and LED light (Ortholux, 3M Unitek). Sixty bovine permanent lower incisors were inserted into PVC tubes containing plaster. The buccal surfaces were cleaned with pumice and water, a...

The design and synthesis of mechanically responsive materials is interesting because they are potential candidates to convert thermal energy into mechanical work. Reported in this paper are thermosalient effects in a series of halogen derivatives of salinazids. The chloro derivative, with higher electronegativity and a weaker inter-halogen bond strength (Cl⋯Cl) exhibits an excellent thermal res...

In the title compound, C(15)H(10)BrFO(2)S, the O atom and the methyl group of the methyl-sulfinyl substituent are located on opposite sides of the plane through the benzofuran fragment. The 4-fluoro-phenyl ring is rotated out of the benzofuran plane, as indicated by a dihedral angle of 26.23 (5)°. The crystal structure is stabilized by a non-classical inter-molecular C-H⋯O hydrogen bond and a B...

In the title compound, C(15)H(10)ClFO(2)S, the O atom and the methyl group of the methyl-sulfinyl substituent are located on opposite sides of the plane through the benzofuran fragment. The 4-fluoro-phenyl ring is rotated out of the benzofuran plane, making a dihedral angle of 25.99 (4)°. The crystal structure is stabilized by a non-classical inter-molecular C-H⋯O hydrogen bond and a Cl⋯O halog...

Heterodimers are constructed containing imidazolium and its halogen-substituted derivatives as Lewis acid. N in its sp³, sp² and sp hybridizations is taken as the electron-donating base. The halogen bond is strengthened in the Cl < Br < I order, with the H-bond generally similar in magnitude to the Br-bond. Methyl substitution on the N electron donor enhances the binding energy. Very little per...

In the title compound, 2C14H8N4O6·CH2Cl2, the di-chloro-methane solvent mol-ecule resides on a crystallographic twofold axis. The mean plane of the phthaliso-imide ring is oriented at a dihedral angle of 32.93 (12)° with respect to the nitro-substituted benzene ring. An intra-molecular N-H⋯O hydrogen bond occurs. The crystal packing features a short Cl⋯O halogen-bond inter-action [3.093 (3) Å].

Hydrogen bond donor catalysis represents a rapidly growing subfield of organocatalysis. While traditional hydrogen bond donors containing N-H and O-H moieties have been effectively used for electrophile activation, activation based on other types of non-covalent interactions is less common. This mini review highlights recent progress in developing and exploring new organic catalysts for electro...

Equimolar qu-anti-ties of tetra-ethyl-ammonium chloride (Et4NCl) and 3,4,5,6-tetra-fluoro-1,2-di-iodo-benzene (o-DITFB or o-C6F4I2) have been co-crystallized in a solution of di-chloro-methane yielding a pure halogen-bonded compound, 3,4,5,6-tetra-fluoro-1,2-di-iodo-benzene-tetra-ethyl ammonium chloride (2/1), Et4N(+)·Cl(-)·2C6F4I2, in the form of translucent needles. [(Et4NCl)(o-C6F4I2)2] pack...