Search results for "bond"

Back Cover: Carboranylphosphinic Acids: A New Class of Purely Inorganic Ligands (Chem. Eur. J. 11/2016)

2016

Toward an understanding of the 1,3-dipolar cycloaddition between diphenylnitrone and a maleimide:bisamide complex. A DFT analysis of the reactivity o…

2007

Abstract The 1,3-dipolar cycloaddition between diphenylnitrone and a maleimide:bisamide complex has been studied using density functional theory (DFT) methods at the B3LYP/6-31G∗ level. The molecular recognition of the bisamide receptor to maleimide favors the formation of the complex through three hydrogen bonds. However, they are not able to produce an efficient acceleration of the cycloaddition because the symmetric substitution of the dipolarophile sites. This poor capability is discussed in base of the transition state structures and the analysis of the reactivity indexes of the reagents.

7-[(3-Chloro-6-methyl-6,11-dihydrodibenzo[c,f][1,2]thiazepin-11-yl)amino]heptanoic acidS,S-dioxide hydrochloride

2012

In the title compound, C(21)H(26)ClN(2)O(4)S(.)Cl, also known as tianeptine hydro-chloride, the seven-membered ring adopts a boat conformation. The dihedral angle between the mean planes of the benzene rings is 44.44 (7)°. There is an intra-molecular hydrogen bond formed via S= O⋯H-N. In the crystal, mol-ecules are connected via pairs of N-H.·O, N-H⋯Cl and O-H⋯Cl hydrogen bonds, forming inversion dimers, which are consolidated by C-H⋯O inter-actions. The dimers are linked by C-H⋯O and C-H⋯Cl inter-actions, forming a two-dimensional network lying parallel to (011).

Ethyl 5-amino-3-(pyridin-4-yl)-1-(2,4,6-trichlorophenyl)-1H-pyrazole-4-carboxylate dimethyl sulfoxide hemisolvate

2012

The asymmetric unit of the title compound, C17H13Cl3N4O2·0.5C2H6OS, contains two almost identical molecules and one dimethyl sulfoxide (DMSO-d6) solvent molecule. The pyrazole ring forms dihedral angles of 54.6 (4) and 80.0 (4)° in one molecule, and dihedral angles of 54.2 (4) and 81.2 (4)° in the other molecule, with the directly attached pyridine and trichlorophenyl rings, respectively. The dihedral angles of the pyridine and trichlorophenyl rings are 51.2 (4) and 52.0 (4)°, respectively. The crystal packing is characterized by intra- and intermolecular hydrogen bonds. The crystal is a nonmeroh…

(Z)-Amino­(2-methyl-3-oxoisoindolin-1-yl­idene)acetonitrile

2009

The asymmetric unit of the title compound, C11H9N3O, contains two independent and nearly identical molecules (A and B). Molecule A can be transformed to B using a rotation of approximately 85° around the [111] direction. Each A molecule is connected to three B molecules via N—H...N and N—H...O hydrogen bonds and vice versa. Centrosymmetrically related molecules of the same residue form π–π interactions with centroid–centroid distances of 4.326 (1) and 3.826 (1) Å for the benzene rings of molecules A and B, respectively.

4-Nitro-phenyl 2-bromo-2-methyl-propano-ate.

2011

In the title compound, C(10)H(10)BrNO(4), the planes of the carboxyl-ate and nitro groups are rotated by 60.53 (13) and 6.4 (3)°, respectively, to the benzene ring. In the crystal, inter-molecular C-H⋯O hydrogen bonds link the mol-ecules into zigzag chains parallel to the c axis.

A second monoclinic polymorph of 2-(3,5-dimethyl-1H-pyrazol-1-yl)-2-hy-droxy-imino-N'-[1-(pyridin-2-yl)ethyl-idene]acetohydrazide.

2013

The title compound, C14H16N6O2, is a second monoclinic polymorph of 2-[1-(3,5-dimeth­yl)pyrazol­yl]-2-hy­droxy­imino-N′-[1-(2-pyrid­yl)ethyl­idene] acetohydrazide, with two crystallographically independent mol­ecules per asymmetric unit. The non-planar mol­ecules are chemically equal having similar geometric parameters. The previously reported polymorph [Plutenko et al. (2012 ▶). Acta Cryst. E68, o3281] was described in space group Cc (Z = 4). The oxime group and the O atom of the amide group are anti with respect to the C—C bond. In the crystal, mol­ecules are connected by N—H⋯N hydrogen bonds into zigzag chains extending along the b axis.

PyridiniumD(+)-10-camphorsulfonate hemihydrate

2002

In the crystal structure of pyridinium d(+)-10-camphor­sulfonate hemihydrate, C5H6N+·C10H15O4S−·0.5H2O, a water mol­ecule lying on a twofold axis serves as a donor of two hydrogen bonds, thus linking two camphor­sulfonate anions. Each anion in its turn acts as a hydrogen-bond acceptor for the NH group of a pyridinium cation.

4-[2-(4-Fluorophenyl)furan-3-yl]pyridine

2009

In the crystal structure of the title compound, C(15)H(10)FNO, the furan ring makes dihedral angles of 40.04 (11) and 25.71 (11)° with the pyridine and 4-fluoro-phenyl rings, respectively. The pyridine ring makes a dihedral angle of 49.51 (10)° with the 4-fluoro-phenyl ring. Non-conventional C-H⋯F and C-H⋯N hydrogen bonds are effective in the stabilization of the crystal structure.

5-(4-Fluoro-phen-yl)-4-(4-pyrid-yl)-1,3-oxazol-2-amine.

2010

In the crystal structure of the title compound, C14H10FN3O, the plane of the isoxazole ring makes dihedral angles of 35.72 (9) and 30.00 (9)°, respectively, with those of the 4-fluorophenyl and pyridine rings. The plane of the 4-fluorophenyl ring makes a dihedral angle of 45.85 (8)° with that of the pyridine ring. The crystal structure is stabilized by intermolecular N—H...N hydrogen bonding. The two types of hydrogen bonds result in two chains, extending along the a axis, which are related by centres of symmetry.