A new ion-pair complex, (C16H14N)2[Ni(C4N2S2)2] or (1-NaMePy)2[Ni(imnt)2], where 1-NaMePy is 1-(4-naphthyl-methyl-ene)pyridinium and imnt is 2,2-di-cyano-ethene-1,1-di-thiol-ate, was obtained by the direct reaction of NiCl2, K2imnt and (1-NaMePy)(+)Br(-) in H2O. The asymmetric unit contains a [1-NaMePy](+) cation and one half of an Ni(imnt)2 (2-) anion. The Ni(II) ion lies on an inversion centr...

Differently substituted pyridinium N-heteroarylaminides have been prepared in one step with good yield from N-aminopyridinium iodide and the corresponding heteroaryl chloride. q 2003 Elsevier Ltd. All rights reserved. For many years conjugated heterocyclic N-ylides, a subgroup of mesomeric betaines, have been widely used as building blocks for the synthesis of fused heterocyclic systems and nat...

A macrocyclization-induced phosphorescence enhancement (MIPE) strategy involving macrocyclization of phosphorescent pyridine/pyridinium units by methylene linkers is reported and proved to have good effectiveness universality.

On the basis of our previous work on DNA fluorophores derived from vinylpyridinium-triphenylamine, we explored the structure space around the electron-rich triphenylamine (TP) core by changing the vinyl bond to an oxazole ring. As 2,5-diaryloxazoles are known to be highly fluorescent and efficient two photon absorbers, we synthesized analogues with two different connections of the oxazole to th...

In the title compound, C(9)H(13)N(2)O(+)·ClO(4) (-), the dihedral angle between the planes of the amide group and the pyridinium fragment is 34.11 (14)°. In the crystal, the cations are connected by N-H⋯O hydrogen bonds between the amide groups into chains extended along the a axis. Hydrogen bonds between the pyridinium N-H group and the perchlorate anions organize the chains into a two-dimensi...

The title compound, C(22)H(22)FN(3), exists as a zwitterion with the negative charge on the dicyano-methanide group and the positive charge on the pyridinium N atom. The mol-ecule adopts a Z conformation about the central C=C bond. The dihedral angle between the pyridinium and benzene rings is 65.65 (5)°. Weak C-H⋯N hydrogen bonding is present in the crystal structure.

In the title salt, C(6)H(9)N(2) (+)·NO(3) (-), the 2-amino-5-methyl-pyridinium cation and the nitrate anion are cyclically linked through pyridinium and amine N-H⋯O hydrogen bonds [graph set R(4) (3)(12)]. These units are extended into a zigzag chain structure lying parallel to the a axis, through a second cyclic R(2) (2)(8) association involving amine N-H⋯O and aromatic C-H⋯O hydrogen bonds to...

In the title coordination polymer, [Cu(C(9)H(8)NO(4))(2)](n), the Cu atom, located on a twofold rotation axis, is four coordinate in a distorted square-planar environment. Each 2,6-dimethyl-pyridinium-3,5-dicarboxyl-ate anion bridges two Cu atoms, forming a two-dimensional coordination polymer. A three-dimensional supra-molecular network is built from N-H⋯O hydrogen bonds involving the pyridini...

This paper describes a convenient approach to the 7-aza-des-A-steroid (6,6a,7,8,9,9a-hexahydro-5H-cyclopenta[h]quinoline) scaffold starting from Grundmann's ketone using two different pyridine annulation protocols. The biological evaluation of the pyridine and pyridinium products revealed that these compounds unexpectedly do not interfere with ergosterol and cholesterol biosynthesis. The pyridi...

The cation of the salt, C(18)H(18)N(2)O(2) (2+)·2NO(3) (-), lies about a twofold rotation axis. The pyridinium ring is almost coplanar with the phenyl-ene ring [dihedral angle between rings = 5.69 (9)°]. The crystal structure shows π-π stacking inter-actions [centroid-centroid distance = 3.70 (1) Å] between the pyridinium rings and the phenyl-ene rings, generating a linear chain structure. The ...