In the title hydrated salt, C13H10Cl2N3O(+)·Cl(-)·3H2O, the organic cation exhibits a dihedral angle of 8.26 (14)° between the mean planes of the pyridinium and benzene rings, and dihedral angles of 8.70 (15) and 15.93 (5)° between the mean planes of the hydrazide group and the benzene and pyridinium rings, respectively. In the crystal, N-H⋯O, N-H⋯Cl, C-H⋯O, C-H⋯Cl, O-H⋯O, O-H⋯N and O-H⋯Cl hydr...

The asymmetric unit of the title salt, (C5H7N2)2[Cr2O7], contains four independent cations and two independent dichromate anions. The crystal structure consists of discrete dichromate anions with an eclipsed conformation stacked in layers parallel to (010) at y = 1/4 and y = 3/4. These layers are linked via 4-amino-pyridinium cations by N-H⋯O and weak C-H⋯O hydrogen bonds, forming a three-dimen...

In this note, we report the discovery of a novel pyridinium chlorochroamte-catalyzed process in which an α-bromomethyl-tetrahydrofuran bond was oxidatively cleaved to give a γ-lactone functionality. The title compound was synthesized from a C15 polybrominated acetogenin compound, isolated from the marine sponge Mycale rotalis, by benzoylation followed by pyridinium chlorochromate-catalyzed oxid...

The chromatographic behaviour of algal chlorophylls under ion-pair reversed-phase liquid chromatography conditions has been tested either on monomeric and polymeric octadecylsilica columns. Three five-carbon amino compounds (pentylamine, piperidine and pyridine), differing in their molecular shapes and chemical properties, have been used as counterions. The monomeric octadecylsilica column did ...

Four halogen and hydrogen bonding rotaxane host systems featuring pyridinium bis-amide-iodotriazole/prototriazole and pyridinium bis-amide-iodotriazolium/prototriazolium axle components have been synthesized by CuAAC-mediated mono-stoppering chloride anion templation and post-rotaxanation methylation reactions. In competitive 45 : 45 : 10 CDCl3-CD3OD-D2O aqueous solvent media, the dicationic ha...

In the title salt, C(6)H(10)N(2) (2+)·2Br(-), the non-H atoms of the 3-methyl-pyridinium unit of the cation are almost coplanar (r.m.s. deviation = 0.0052 Å). In the crystal, the dications and Br anions are linked by a combination of six hydrogen bonds, viz. one N(py)-H⋯Br, two C-H⋯Br and three H(2)N-H⋯Br, into supra-molecular layers, parallel to the bc plane, composed of alternating R(2) (4)(1...

2-monobromomethyl 1,4-dihydropyridines is selectively synthesized by bromination of the parent compound by 1.1 equivalents of pyridinium bromide perbromide in dichloromethane/pyridine at -20 °c. the same reagent in dichloromethane at 0 °c produce the 2,6-bis(bromomethyl) 1,4-dihydropyridines.

A series of pyridinium and bipyridinium salts were prepared their catalytic properties evaluated in the aza-Diels-Alder reaction between imines Danishefsky diene. Depending on substituents pyridinium/bipyridinium rings nature counterion, two mechanisms activation demonstrated. In case non-substituted rings, substrate is activated through charge transfer involving aryl ring C-side imine. When ha...

A new class of boronium and borenium cations are prepared by reaction of pyridinium hydrochloride with pyridine stabilized borabenzene derivatives.

The title compound, C(6)H(10)N(2) (2+)·2Cl(-), contains a network of 4-(ammonio-meth-yl)pyridinium cations and chloride anions which are inter-connected by N-H⋯Cl hydrogen bonds. The crystal packing is also influenced by inter-molecular π-π stacking inter-actions between identical anti-parallel organic cations with a face-to-face distance of ca 3.52 Å.