The asymmetric unit of the title salt, (C12H11BrN)2[Ni(C4N2S2)2], consists of one 1-(4-bromo-benz-yl)pyridinium cation and one half of a complex [Ni(mnt)2](2-) (mnt(2-) is the maleo-nitrile-dithiol-ate dianion). The Ni(2+) ion is located on an inversion centre and is coordinated by four S atoms from two mnt(2-) ligands, exhibiting a square-planar coordination environment. In the cation, the pla...

In the crystal structure of the title compound, C(5)H(8)N(3) (+)·H(2)PO(4) (-), N-H⋯O hydrogen bonds, involving the unprotonated amino-group and the NH(+) group in the pyridinium ring and dihydrogenphosphate O atoms, link the cations and anions. A long chain-like stacking of dihydrogenphosphate anions along the c-axis direction is constructed by O-H⋯O hydrogen bonds. Also along the c-axis direc...

The title mol-ecular salt, C8H13N2 (+)·Br(-), crystallizes with two independent 3-amino-pyridinium cations and two bromide anions in the asymmetric unit (Z' = 2). In the pyridine ring, the N atom is alkyl-ated by a propyl group. The dihedral angle between the mean planes of the pyridinium ring and the propyl group is 84.84 (2)° in cation A, whereas the corresponding angle is 89.23 (2)° in catio...

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.