A second monoclinic polymorph of 2,4-dimethyl-anilinium chloride, C(8)H(12)N(+)·Cl(-), (I), is reported. The unit-cell dimensions differ from those of the first reported monoclinic form, (II) [Yao (2010 ▶). Acta Cryst. E66, o1563]. Nevertheless, both compounds crystallize in the monoclinic space group P2(1)/n. As in (II), the protonated amine group in (I) acts as a hydrogen-bond donor to the ch...

In the title compound, C10H8N4S2, comprising fused six-, six- and five-membered rings, the mol-ecule is close to being planar (r.m.s. deviation of the non-H atoms = 0.041 Å). The S-bound methyl group is folded away from the single N atom of the triazole ring and the NH group of the six-membered ring, allowing for the formation of centrosymmetric eight-membered {⋯HNCN}2 synthons in the crystal. ...

The title compound, C(33)H(45)NO(10), has an aconitine carbon skeleton with four six-membered rings and two five-membered rings. The five-membered rings adopt envelope configurations and the six-membered N-containing heterocyclic ring displays a chair conformation. Two intra-molecular O-H⋯O hydrogen bonds occur.

The ability of the present semiempirical quantum mechanics methods are surveyed for reproducing the transannular interaction in the bifunctional N-phenyl-5-azocanones. The AM1 method is the best with the order of reliability being Am1, PM3, MNDO and MINDO/3. AM1 calculations were then carried out for quantification of transannular interaction. The n(o) ionization potential has be...

In the presence of water and amines etherate bicyclic Al2(OSiPh2OSiPh2O)3 (II a) can be used to generate novel alumosiloxane polycycles like [O(Ph2SiOSiPh2)O−]2Al2O[O(Ph2SiOSiPh2)O] ⋅ 2 H2N+Et2 (1), [O(Ph2SiOSiPh2)O−]2Al2[O(Ph2Si)O]2 HN+Et3 (2), [O(Ph2SiOSiPh2)O−]2Al2[O(Ph2SiOSiPh2)O]2 (3 a, 3 b), which crystallizes in two different phases, HN+(CH2CH2)3N (4). As a common structural feature thes...

A metastable carbon nanotube with single, double, and triple bonds has been predicted from ab initio simulation. It results from the relaxation of an ideal carbon nanotube with chirality (2,1), without any potential barrier between the ideal nanotube and the new structure. Ten-membered carbon rings are formed by breaking carbon bonds between adjacent hexagons; eight-membered rings, already pres...

The title amine, C(13)H(14)N(2), is twisted with a dihedral angle between the rings of 60.07 (9)°. The amine N-H group and pyridine N atom are syn allowing for the formation of centrosymmetric eight-membered {⋯HNCN}(2) synthons via N-H⋯N hydrogen bonds. The two-mol-ecule aggregates are sustained in the three-dimensional crystal packing via C-H⋯π and π-π inter-actions [centroid-centroid distance...

The copper phosphinimide complexes [Cu{μ-N[double bond, length as m-dash]PR3}]4 (1, R = NMe2 and 2, R = Ph) were obtained in good yields from the reactions of Cu[Mes] (Mes = mesityl, C6H2Me3-2,4,6) with the corresponding iminophosphoranes, HNPR3. The molecular structures of 1 and 2 reveal the presence of planar eight-membered {Cu4N4} rings which contrasts with the saddle-shaped {M4N4} rings fou...

Although isolated nonhexagonal carbon rings in graphene are associated with strain relaxation and curvature, dense ordered arrangements of four-, five-, eight-membered strained carbon–carbon bonds can tile 2D planar layers. Using the Boltzmann transport equation formalism combination density functional theory calculations, how presence impacts thermal conductivity three allotropes: T-graphene (...

EPLERENONE [SYSTEMATIC NAME: 7α-(methoxy-carbon-yl)-3-oxo-9α,11-ep-oxy-17α-pregn-4-ene-21,17-carbolactone], an aldo-sterone receptor antagonist, crystallizes from ethanol as a monosolvate, C(24)H(30)O(6)·C(2)H(6)O. The eplerenone mol-ecule has two five-membered rings, three six-membered rings and one three-membered ring. Both five-membered rings display envelope conformations, while the three s...