Crystal Structures of Neutral Cobalt(III) Complexes:  Common Hydrogen-Bonding Patterns Observed in Compounds of Different Molecular Structures

2001 ◽  
Vol 1 (2) ◽  
pp. 143-149 ◽  
Author(s):  
Hyungphil Chun ◽  
Ivan Bernal
1981 ◽  
Vol 34 (10) ◽  
pp. 2095 ◽  
Author(s):  
AJ Finney ◽  
MA Hitchman ◽  
CL Raston ◽  
GL Rowbottom ◽  
BW Skelton ◽  
...  

The crystal and molecular structures of the compounds [Ni(py)4(ONO)2],2py, [Ni(γmpy),(ONO)2] and [Ni(prz)4(ONO)2] are reported.�All three are trans nitrito complexes, the pyridine (py) compound containing two pyridine molecules of solvation. The aromatic rings in the first two complexes adopt 'paddle wheel' conformations with pitch angles varying between 40 and 70�. The nitrite ions are positioned so as to minimize repulsive interactions with the amines, and it seems likely that these groups bond through oxygen rather than nitrogen because this allows a lesser degree of interligand steric interference. The amine rings in [Ni(prz)4(ONO)2] are orthogonal to the plane containing the nickel and coordinated pyrazole nitrogen atoms; the nitrito groups are disordered between two inequivalent positions, each of which involves hydrogen bonding with the pyrazole NH groups. The nitrite infrared frequencies are similar to those observed for other nickel(II) nitrito complexes except that the antisymmetric NO stretching mode of one of the groups in the pyrazole complex is much lower in energy than expected, being in the range normally associated with a nitrogen-bonded or chelated nitrite group. It is suggested that this deviation may be caused by the hydrogen bonding in the complex. The electronic spectra of the compounds yield 10Dq values of 9100 and 8500 cm-1 for the nitrite ligands in [Ni(py)4(ONO)2] and Ni(prz)4(ONO)2], respectively, placing the nitrito group towards the weaker end of the spectro-chemical series.


2014 ◽  
Vol 70 (2) ◽  
pp. 241-249 ◽  
Author(s):  
Wilhelm Maximilian Hützler ◽  
Ernst Egert

The preferred hydrogen-bonding patterns in the crystal structures of 5-propyl-2-thiouracil, C7H10N2OS, (I), 5-methoxy-2-thiouracil, C5H6N2O2S, (II), 5-methoxy-2-thiouracil–N,N-dimethylacetamide (1/1), C5H6N2O2S·C4H9NO, (IIa), 5,6-dimethyl-2-thiouracil, C6H8N2OS, (III), 5,6-dimethyl-2-thiouracil–1-methylpyrrolidin-2-one (1/1), C6H8N2OS·C5H9NO, (IIIa), 5,6-dimethyl-2-thiouracil–N,N-dimethylformamide (2/1), 2C6H8N2OS·C3H7NO, (IIIb), 5,6-dimethyl-2-thiouracil–N,N-dimethylacetamide (2/1), 2C6H8N2OS·C4H9NO, (IIIc), and 5,6-dimethyl-2-thiouracil–dimethyl sulfoxide (2/1), 2C6H8N2OS·C2H6OS, (IIId), were analysed. All eight structures containR22(8) patterns. In (II), (IIa), (III) and (IIIa), they are formed by two N—H...S hydrogen bonds, and in (I) by alternating pairs of N—H...S and N—H...O hydrogen bonds. In contrast, the structures of (IIIb), (IIIc) and (IIId) contain `mixed'R22(8) patterns with one N—H...S and one N—H...O hydrogen bond, as well asR22(8) motifs with two N—H...O hydrogen bonds.


Author(s):  
Haruki Sugiyama

The crystal structures of two salt crystals of 2,2-bis(4-methylphenyl)hexafluoropropane (Bmphfp) with amines, namely, dipyridinium 4,4′-(1,1,1,3,3,3-hexafluoropropane-2,2-diyl)dibenzoate 4,4′-(1,1,1,3,3,3-hexafluoropropane-2,2-diyl)dibenzoic acid, 2C5H6N+·C17H8F6O4 2−·C17H10F6O4, (1), and a monohydrated ethylenediammonium salt ethane-1,2-diaminium 4,4′-(1,1,1,3,3,3-hexafluoropropane-2,2-diyl)dibenzoate monohydrate, C2H10N2 2+·C17H8F6O4 2−·H2O, (2), are reported. Compounds 1 and 2 crystallize, respectively, in space group P21/c with Z′ = 2 and in space group Pbca with Z′ = 1. The crystals of compound 1 contain neutral and anionic Bmphfp molecules, and form a one-dimensional hydrogen-bonded chain motif. The crystals of compound 2 contain anionic Bmphfp molecules, which form a complex three-dimensional hydrogen-bonded network with the ethylenediamine and water molecules.


Author(s):  
Marek Daszkiewicz ◽  
Agnieszka Mielcarek

Crystal structures of (H2m4na)NO3(1), (H2m4na)HSO4(2), (H2m4na)2SiF6(3) and (H2m4na)2SiF6·2H2O (4), where 2m4na = 2-methyl-4-nitroaniline, are presented. Two layers of interactions occur in the structures, N—H...O/F hydrogen bonds and interactions with the nitro group. Although diverse, hydrogen-bonding patterns are compared with each other by means of interrelations among elementary graph-set descriptors and descriptors of hydrogen-bonding patterns. Using mathematical relations, the gradual expansion of the ring patterns was shown in the crystal structures. Parallel and perpendicular arranged nitro groups form weak π(N)NO2...π(O)NO2and π(N)NO2...ONO2interactions, respectively. The πNO2...πringinteraction has an impact to the stabilization of parallel oriented nitro groups. Generally, weak interactions constructed by the nitro group occur in the studied crystals as follows: π(N)NO2...π(O)NO2, πring...πring, C—H...O (1); π(N)NO2...π(O)NO2, π(N)NO2...ONO2(2); π(N)NO2...π(O)NO2, π(N)NO2...ONO2(3); C—H...O (4).


IUCrJ ◽  
2013 ◽  
Vol 1 (1) ◽  
pp. 61-73 ◽  
Author(s):  
Sándor L. Bekö ◽  
Edith Alig ◽  
Martin U. Schmidt ◽  
Jacco van de Streek

Inositol, 1,2,3,4,5,6-hexahydroxycyclohexane, exists in nine stereoisomers with different crystal structures and melting points. In a previous paper on the relationship between the melting points of the inositols and the hydrogen-bonding patterns in their crystal structures [Simperleret al.(2006).CrystEngComm8, 589], it was noted that although all inositol crystal structures known at that time contained 12 hydrogen bonds per molecule, their melting points span a large range of about 170 °C. Our preliminary investigations suggested that the highest melting point must be corrected for the effect of molecular symmetry, and that the three lowest melting points may need to be revised. This prompted a full investigation, with additional experiments on six of the nine inositols. Thirteen new phases were discovered; for all of these their crystal structures were examined. The crystal structures of eight ordered phases could be determined, of which seven were obtained from laboratory X-ray powder diffraction data. Five additional phases turned out to be rotator phases and only their unit cells could be determined. Two previously unknown melting points were measured, as well as most enthalpies of melting. Several previously reported melting points were shown to be solid-to-solid phase transitions or decomposition points. Our experiments have revealed a complex picture of phases, rotator phases and phase transitions, in which a simple correlation between melting points and hydrogen-bonding patterns is not feasible.


2018 ◽  
Vol 74 (11) ◽  
pp. 1553-1560
Author(s):  
H. Purandara ◽  
Sabine Foro ◽  
B. Thimme Gowda

The crystal structures of N-(4-methylbenzenesulfonyl)glycine hydrazone and four derivatives with four different substituents have been investigated, namely, (E)-N-{2-[2-(benzylidene)hydrazinyl]-2-oxoethyl}-4-methylbenzenesulfonamide, C16H17N3O3S, (I), (E)-N-{2-[2-(4-bromobenzylidene)hydrazinyl]-2-oxoethyl}-4-methylbenzenesulfonamide, C16H16BrN3O3S, (II), (E)-N-{2-[2-(4-chlorobenzylidene)hydrazinyl]-2-oxoethyl}-4-methylbenzenesulfonamide, C16H16ClN3O3S, (III), (E)-N-(2-{2-[4-(dimethylamino)benzylidene]hydrazinyl}-2-oxoethyl)-4-methylbenzenesulfonamide, C18H22N4O3S, (IV), and (E)-N-{2-[2-(4-methoxybenzylidene)hydrazinyl]-2-oxoethyl}-4-methylbenzenesulfonamide, C17H19N3O4S, (V). The molecules in all five crystal structures show similar conformations and hydrogen-bonding patterns. The central part of the molecule, i.e. C—C—N—N=C, is almost linear in all the structures, with the C—C—N—N torsion angles ranging from −178.3 (1) to −180.0 (2)° and the C—N—N=C torsion angles ranging from −178.5 (4) to −179.8 (3)°. The conformation of the N—H and C=O bonds in the amide group of the hydrazone part is syn in all the compounds. In all the structures, sulfonamide and hydrazone dimers with R 2 2(8) ring motifs are observed, which are further augmented by C—H...O interactions. A common feature of each of (I)–(V) is the formation of sulfonamide and hydrazone dimers with an R 2 2(8) ring motif. Hirshfeld surface analyses gave fingerprint plots for H...H, O...H/H...O, N...H/H...N, C...H/H...C and other contacts. The H...H contacts show large surfaces, whereas the O...H plots show the presence of O...H/O...H contacts with the two characteristic long sharp spikes.


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