PMCC PMCC

Search tips
Search criteria

Advanced
Results 1-25 (187779)

Clipboard (0)
None

Related Articles

1.  {2,2′-[3-Aza­pentane-1,5-diylbis(nitrilo­methyl­idyne)]dipyrrol-1-yl}(4-methyl­pyridine)cobalt(III) tetra­phenyl­borate 
The title compound, [Co(C14H17N5)(C6H7N)](C24H20B) or [Co{(pyrrole)2dien}(4-Mepy)]BPh4 where (pyrrole)2dien is 2,2′-[(3-aza­pentane-1,5-diylbis(nitrilo­methyl­idyne)]dipyrrole and 4-Mepy is 4-methyl­pyridine, contains a penta­dentate (pyrrole)2dien ligand furnishing an N5 set, such that two of the pyrrole N atoms and two of the dien N atoms occupy the equatorial positions while one of the imine N atoms of the (pyrrole)2dien ligand occupies the axial position. The 4-methyl­pyridine ligand occupies an axial position trans to one of the imine N atoms of the penta­dentate ligand. In the observed conformation of the penta­dentate ligand, the pyrrole rings attain asymmetrical positions owing to the structural demands. The geometry of the resulting CoN6 coordination can be described as distorted octa­hedral.
doi:10.1107/S1600536810006112
PMCID: PMC2983608  PMID: 21580267
2.  (2Z,2′Z)-Diethyl 3,3′-[butane-1,4-diylbis(aza­nedi­yl)]bis­(but-2-enoate) 
The whole mol­ecule of the title β-enamino­ester, C16H28N2O4, is generated by a crystallographic inversion center, situated at the mid-point of the central C—C bond of the 1,4-diamino­butane segment. There are two intra­molecular N—H⋯O hydrogen bonds that generate S(6) ring motifs. This leads to the Z conformation about the C=C bonds [1.3756 (17) Å]. The mol­ecule is S-shaped with the planar central 1,4-diamino­butane segment [maximum deviation for non H-atoms = 0.0058 (13) Å] being inclined to the ethyl butyl­enonate fragment [C—C—O—C—C=C—C; maximum deviation = 0.0710 (12) Å] by 15.56 (10)°. In the crystal, mol­ecules are linked via C—H⋯O inter­actions, leading to the formation of an undulating two-dimensional network lying parallel to the bc plane.
doi:10.1107/S1600536812036823
PMCID: PMC3470214  PMID: 23125658
3.  2,2′-[(Propane-1,3-diyldinitrilo)bis­(phenyl­methyl­idyne)]diphenol 
In the title mol­ecule, C29H26N2O2, there are two strong intra­molecular O—H⋯N hydrogen bonds involving the hydr­oxy and imine groups, forming S(6) ring motifs. The dihedral angles between adjacent phenyl rings and phenol-containing planes are 85.27 (19) and 91.38 (18)°. In the crystal structure, weak inter­molecular C—H⋯O hydrogen bonds connect mol­ecules into a two-dimensional network.
doi:10.1107/S1600536810011189
PMCID: PMC2983949  PMID: 21580567
4.  {2,2′-[1,1′-(3-Aza­pentane-1,5-diyl­dinitrilo)diethyl­idyne]diphenolato}(piperidine)cobalt(III) tetra­phenyl­borate 
The title compound, [Co(C20H23N3O2)(C5H11N)](C24H20B) or [Co{(Me-sal)2dien}(pprdn)]BPh4, where (Me-sal)2dien is 2,2′-[1,1′-(3-aza­pentane-1,5-diyldinitrilo)diethyl­idyne]diphenolate and pprdn is piperidine, contains a penta­dentate (Me-sal)2dien ligand furnishing an N3O2 set, such that two of the N and one of the O atoms of the salicyl­idene rings define three positions of an equatorial plane, whereas the secondary amine N atom and the other O atom of the salicyl­idene lie in axial positions. The piperidine ligand occupies an equatorial position trans to one of the imine N atoms of the salicyl­idene. In the observed conformation of the penta­dentate ligand, the salicyl­idene rings attain asymmetrical positions owing to the structural demands. The geometry of the resulting CoN4O2 coordination can be described as distorted octa­hedral. The asymetric unit contains two formula units.
doi:10.1107/S1600536808003875
PMCID: PMC2960776  PMID: 21201867
5.  [Oxalylbis(aza­nedi­yl)]bis­{[amino­(2-pyrid­yl)methyl­ene]ammonium} 
The title compound, C14H16N8O2 2+·2ClO4 −, was prepared by reaction of bis­[amino­(2-pyrid­yl)methyl­ene]oxalohydrazide with perchloric acid. The mol­ecular symmetry is Ci and thus the asymmetric unit comprises one half-mol­ecule. The dihedral angle between the aromatic ring and the plane of the oxamide group is 70.8 (3)°. The perchlorate anions and the cations are connected by inter­molecular N—H⋯O hydrogen bonds.
doi:10.1107/S1600536809009015
PMCID: PMC2969094  PMID: 21582507
6.  Dimethyl 3,3′-diphenyl-2,2′-[(S)-thio­phene-2,5-diylbis(carbonyl­aza­nedi­yl)]dipropano­ate 
The asymmetric unit of the title compound, C26H26N2O6S, contains two independent mol­ecules; each has twofold symmetry with the S atom and the mid-point of the C—C bond of the thio­phene ring located on a twofold rotation axis. In the two mol­ecules, the terminal benzene rings are oriented at dihedral angles of 65.8 (3) and 63.5 (3)° with respect to the central thio­phene rings. The meth­oxy­carbonyl group of one mol­ecule is disordered over two positions with site-occupancy factors of 0.277 (12) and 0.723 (12). Inter­molecular N—H⋯O hydrogen bonding is present in the crystal structure.
doi:10.1107/S1600536810033210
PMCID: PMC3007902  PMID: 21588721
7.  Bis{μ-2,2′-[(3-aza­pentane-1,5-di­yl)bis­(nitrilo­methyl­idyne)]diphenolato}dicopper(II) dimethyl sulfoxide disolvate 
The title compound, [Cu2(C18H19N3O2)2]·2C2H6OS or [Cu2(SalenN3H)2]·2DMSO, where SalenN3H is the multidentate Schiff base 2,2′-[(3-aza­pentane-1,5-di­yl)bis­(nitrilo­methyl­idyne)]diphenolate dianion and DMSO is dimethyl sulfoxide, is a solvated dinuclear CuII complex. The neutral complex is built from two Cu(SalenN3H) units related by an inversion center. All heteroatoms in the Schiff bases coordinate the CuII ions, which display highly distorted trigonal bipyramidal geometries. The solvent mol­ecules are located in the structural voids of the complex and are disordered over two positions with occupancies of 0.642 (15) and 0.358 (15). The previously characterized acetone disolvate of the same complex presents identical mol­ecular and crystal structures, and crystallizes with cell parameters very close to those of the DMSO disolvate reported here.
doi:10.1107/S1600536808008544
PMCID: PMC2961312  PMID: 21202185
8.  6,6′-Dimeth­oxy-2,2′-[2,2-dimethyl­propane-1,3-diylbis(nitrilo­methyl­idyne)]diphenol 
The title Schiff base compound, C21H26N2O4, exhibits two crystallographically independent mol­ecules in the asymmetric unit with similar conformations. The imino groups are coplanar with the benzene rings; the maximum deviations of the N atoms from the planes comprising the benzene rings and the imino groups are −0.037 (4), 0.013 (4), −0.021 (5), and 0.008 (5) Å. The dihedral angles between the benzene rings in the two mol­ecules are 53.64 (17) and 51.93 (17)°. Strong intra­molecular O—H⋯N hydrogen bonds generate S(6) ring motifs. The N atoms are also in close proximity to the H atoms of the dimethyl­propane groups, with H⋯N distances between 2.54 and 2.75 Å. The crystal structure is further stabilized by weak inter­molecular C—H⋯O hydrogen bonds, weak inter­molecular C—H⋯π inter­actions and π–π contacts involving the imine C atom and two C atoms from the adjacent benzene rings.
doi:10.1107/S1600536808038002
PMCID: PMC2967940  PMID: 21581654
9.  2,2′-{[4,6-Bis(octyl­amino)-1,3,5-triazin-2-yl]aza­nedi­yl}diethanol 
In the title compound, C23H46N6O2, the two hy­droxy groups are located on opposite sides of the triazine ring. One of the hy­droxy groups links with the triazine N atom via an intra­molecular O—H⋯N hydrogen bond. Inter­molecular O—H⋯N and N—H⋯O hydrogen bonding is observed in the crystal structure. π–π stacking is also observed between parallel triazine rings of adjacent mol­ecules, the centroid–centroid distance being 3.5944 (14) Å.
doi:10.1107/S1600536812003856
PMCID: PMC3295417  PMID: 22412528
10.  Di-tert-butyl 2,2′-[(2-hydroxy­ethyl)aza­nedi­yl]diacetate 
In the title compound, C14H27NO5, the hydr­oxy group and one of the acetate carbonyl O atoms are linked by an intra­molecular O—H⋯O hydrogen bond, forming an eight-membered ring. This inter­action gives rise to an asymmetric mol­ecular conformation.
doi:10.1107/S1600536809049022
PMCID: PMC2971910  PMID: 21578883
11.  2,2′-{1,1′-[Pentane-1,5-diyl­bis(oxy­nitrilo)]­diethyl­idyne}diphenol 
In the title compound, C21H26N2O4, there is half a mol­ecule in the asymmetric unit with a crystallographic twofold rotation axis passing through the central C atom of the –CH=N—O—(CH2)5—O—N=CH– bridge. The dihedral angle formed by the two benzene rings is 80.85 (2)°. Strong intra­molecular O—H⋯N and C—H⋯O hydrogen bonds help to establish the molecular conformation. There are also weak inter­molecular π–π stacking inter­actions between neighbouring benzene rings [centroid–centroid separation = 3.502 (3) Å].
doi:10.1107/S160053680803136X
PMCID: PMC2959680  PMID: 21580925
12.  6,6′-Dimethyl-2,2′-[oxalylbis(aza­nedi­yl)]dipyridinium dichloride acetonitrile solvate 
In the crystal structure of the title compound, C14H16N4O2 2+·2Cl−·CH3CN, weak inter­molecular N—H⋯Cl hydrogen bonds are found between the H atoms bound to the pyridine and amine N atoms and the chloride anions. The asymmetric unit consits of one half cationic mol­ecule which is located on a centre of inversion, one chloride anion in a general position and one half acetonitrile mol­ecule which is located on a twofold axis. Because of symmetry, the C—H hydrogens of the acetonitrile solvent mol­ecule are disordered over two orientations.
doi:10.1107/S1600536810033519
PMCID: PMC3007829  PMID: 21588722
13.  {2,2′-[(2,2-Dimethylpropane-1,3-diyl­dinitrilo)bis(phenylmethylidyne)]di­phenolato}copper(II) 
The complete mol­ecule of the title complex, [Cu(C31H28N2O2)], is generated by the application of twofold symmetry; the Cu and CMe2 atoms lie on the axis. The geometry around the CuII atom is distorted square-planar. The dihedral angle between the two phenyl rings is 76.0 (3) °. The crystal packing is stabilized by inter­molecular C—H⋯π inter­actions.
doi:10.1107/S1600536811028844
PMCID: PMC3212202  PMID: 22090904
14.  {6,6′-Dimeth­oxy-2,2′-[2,2-dimethyl­propane-1,3-diylbis(nitrilo­methyl­idyne)]diphenolato}nickel(II) 1.78-hydrate 
In the title complex, [Ni(C21H24N2O4)]·1.78H2O, the NiII ion has a slightly distorted planar geometry, coordinated by the two N and two O atoms of the tetra­dentate Schiff base ligand, with a mean deviation of 0.272 Å from the NiN2O2 plane. The N and O donor atoms are mutually cis. The dihedral angle between two benzene rings of the ligand is 38.86 (8)°. There are also three solvent water mol­ecules, two of which lie across different crystallographic twofold rotation axes; one of these is partially occupied with a refined occupancy factor of 0.570 (7). The water mol­ecules are linked together as tetra­mers in R 2 2(8) ring motifs, which also connect two neighbouring mol­ecules of the complex through a network of O—H⋯O hydrogen bonds. The crystal structure is further stabilized by inter­molecular C—H⋯O and C—H⋯π inter­actions, which link neighbouring mol­ecules into extended chains along the b axis. Other inter­esting features of the crystal structure are the short inter­molecular C⋯C [3.204 (3)–3.365 (3) Å] and the C⋯O [3.199 (2)–3.205 (2) Å] contacts which are shorter than the sum of the van der Waals radii of these atoms.
doi:10.1107/S1600536809014500
PMCID: PMC2977614  PMID: 21583800
15.  (E,E)-4,4′-Dichloro-2,2′-[azinobis(phenyl­methyl­idyne)]diphenol 
The title compound, C26H18Cl2N2O2, was synthesized by the reaction of (5-chloro-2-hydroxy­phen­yl)(phen­yl)methanone with hydrazine hydrate. The mol­ecule possesses a crystallographically imposed centre of symmetry at the mid-point of the N—N bond. The conformation of the mol­ecule is stabilized by an intra­molecular O—H⋯N hydrogen bond.
doi:10.1107/S1600536809041427
PMCID: PMC2971269  PMID: 21578361
16.  4,4′-[Propane-1,2-diyl­bis(nitrilo­methyl­idyne)]­dibenzo­nitrile–4,4′-[ethane-1,2-diylbis(nitrilo­methyl­idyne)]dibenzonitrile [0.796 (2)/0.204 (2)] 
The title cocrystal, 0.796C19H16N4·0.204C18H14N4, is a disordered mixture of two potentially bidentate Schiff base ligands. The difference in the two components of the cocrystal is the replacement of the methyl group in the linkage between the imine N atoms in the major component of the Schiff base ligand by an H atom. The imino (C=N) functional groups are coplanar with the benzene rings (only the major component) and extend in opposite directions (both components). Inter­molecular π–π inter­actions with a centroid-to-centroid distance of 3.7371 (8) Å are observed in the crystal packing.
doi:10.1107/S1600536808031097
PMCID: PMC2959562  PMID: 21580986
17.  {2,2′-[(2,2-Dimethyl­propane-1,3-diyl­dinitrilo)­bis­(phenyl­methyl­idyne)]­diphenolato}nickel(II) 
The asymmetric unit of the title complex, [Ni(C31H28N2O2)], comprises two crystallographically independent mol­ecules. The geometry around the NiII atom in each mol­ecule is distorted square planar. The dihedral angles between the two phen­oxy rings in each mol­ecule are 17.8 (4) and 36.5 (4)°. The crystal packing is stabilized by weak π–π inter­actions [centroid–centroid distance = 3.758 (5) Å] and C—H⋯π inter­actions.
doi:10.1107/S1600536811029813
PMCID: PMC3200906  PMID: 22065816
18.  2,2′-[1,2-Phenyl­enebis(aza­nedi­yl)]di­aceto­nitrile 
The title compound, C10H10N4, shows chemical but not crystallographic C 2 symmetry. The two cyano­methyl groups are located in an anti position with respect to the aromatic ring. In the crystal, mol­ecules form parallel ladder-like tapes linked through two N—H⋯N hydrogen bonds. Further weak intra­molecular N—H⋯N hydrogen bonding is responsible for the elongation of one of the Caromatic—N bonds.
doi:10.1107/S1600536812047538
PMCID: PMC3589011  PMID: 23476247
19.  Dimethyl 3,3′-diphenyl-2,2′-[(S)-thio­phene-2,5-diylbis(carbonyl­aza­nedi­yl)]dipropano­ate tetra­hydro­furan monosolvate 
The title compound, C26H26N2O6S·C4H8O, a solvated bis-amide derivative, is also a chiral amino acid ester with l-phenyl­alanine methyl ester groups as amine substituents. The thio­phene-2,5-dicarboxamide core approximates C 2 point symmetry. The tetra­hydro­furan solvent mol­ecule is linked to the main mol­ecule through an inter­molecular N—H⋯O hydrogen bond. The central ring makes dihedral angles of 90.0 (2) and 76.5 (2)° with the pendant rings.
doi:10.1107/S1600536810034410
PMCID: PMC2983431  PMID: 21587488
20.  4,4′-Dimethyl-2,2′-[(3-aza­pentane-1,5-di­yl)bis­(nitrilo­methyl­idyne)]diphenol 
In the crystal structure of the title Schiff base, C20H25N3O2, the salicylaldimine groups at each end of the mol­ecule are essentially planar and make a dihedral angle of 84.94 (3)° with each other. There are strong intra­molecular O—H⋯N hydrogen bonds and a weak inter­molecular N—H⋯O hydrogen bond.
doi:10.1107/S1600536808018837
PMCID: PMC2961844  PMID: 21202971
21.  A second tricilinc polymorph of 6,6′-dieth­oxy-2,2′-[propane-1,2-diylbis(nitrilo­methyl­idyne)]diphenol 
The title Schiff base compound, C21H26N2O4, is a second triclinic polymorph of a previously reported room-temperature structure [Jia (2009 ▶). Acta Cryst. E65, o646]. Strong intra­molecular O—H⋯N hydrogen bonds generate S(6) ring motifs. Inter­molecular C—H⋯O inter­actions link neighbouring mol­ecules into dimers with an R 2 2(16) ring motif. The mean planes of the two benzene rings are almost perpendicular to each other, making a dihedral angle of 88.24 (5)°. An inter­esting feature of the crystal structure is the intermolecular short C⋯O [3.1878 (13) Å] contact which is shorter than the sum of the van der Waals radii of the relevant atoms. The crystal structure is further stabilized by inter­molecular C—H⋯π and π–π inter­actions [centroid–centroid distance = 3.7414 (6) Å]. The structure has a stereogenic centre but the space group is centrosymmetric, so the mol­ecule exists as a racemate.
doi:10.1107/S1600536809008137
PMCID: PMC2968989  PMID: 21582458
22.  4,4′-Dichloro-2,2′-[2,2-dimethyl­propane-1,3-diylbis(nitrilo­methyl­idyne)]diphenol 
The crystal of the title Schiff base compound, C19H20Cl2N2O2, contains of two crystallographically independent mol­ecules with similar conformations. In each mol­ecule, two intramolecular O—H⋯N bonds generate S(6) motifs. The N atoms are also in close proximity to two H atoms of the dimethyl­propane groups, with H⋯N distances between 2.59 and 2.62 Å. The imine group is coplanar with the benzene ring. The dihedral angles between the benzene rings in the two independent mol­ecules are 58.20 (12) and 47.95 (12)°. The structure displays short inter­molecular Cl⋯Cl [3.3869 (11) Å] and Cl⋯O [3.175 (2)–3.204 (2) Å] inter­actions. The crystal structure is further stabilized by weak inter­molecular C—H⋯O, C—H⋯π and π–π [centroid–centroid distances 3.6416 (13)–3.8705 (14) Å] inter­actions.
doi:10.1107/S1600536808038014
PMCID: PMC2967979  PMID: 21581707
23.  {6,6′-Dieth­oxy-2,2′-[2,2-dimethyl­propane-1,3-diylbis(nitrilo­methyl­idyne)]diphenolato}copper(II) monohydrate 
In the title complex, [Cu(C23H28N2O4)]·H2O, the CuII ion has a distorted planar geometry, coordinated by the N2O2 unit of the tetra­dentate Schiff base ligand. The asymmetric unit comprises one complex mol­ecule and a water mol­ecule of crystallization. The water H atoms form bifurcated O—H⋯(O,O) inter­molecular hydrogen bonds with the O atoms of the phenolate and eth­oxy groups with R12(5) and R12(6) ring motifs, which may, in part, influence the mol­ecular configuration. The dihedral angle between the two O—Cu—N coordination planes is 31.02 (6)° and the dihedral angle between the two benzene rings is 34.98 (7)°. In the crystal structure, mol­ecules are linked together by inter­molecular C—H⋯O inter­actions, forming extended chains along the a axis. The crystal structure is further stabilized by inter­molecular C—H⋯π and π–π [centroid–centroid = 3.5068 (13) Å] inter­actions.
doi:10.1107/S1600536809012859
PMCID: PMC2977574  PMID: 21583760
24.  {3,3′,5,5′-Tetra­meth­oxy-2,2′-[ethane-1,2-diylbis(nitrilo­methyl­idyne)]diphenolato}nickel(II) 
The title square-planar nickel complex, [Ni(C20H22N2O6)], has Ni—N and Ni—O bond lengths of 1.8448 (14)/1.8478 (14) and 1.8536 (12)/1.8520 (12) Å. There is a slight twist in the two benzene rings at each end of the complex [dihedral angle = 11.11 (5)°]. All the atoms of the meth­oxy substitutents are in the plane of the ring to which they are attached except for one which deviates slightly [0.365 (3) Å]. In the crystal, weak C—H⋯O inter­molecular inter­actions connect the mol­ecules.
doi:10.1107/S1600536810016041
PMCID: PMC2979626  PMID: 21579278
25.  {3,3′,5,5′-Tetra­meth­oxy-2,2′-[ethane-1,2-diylbis(nitrilo­methyl­idyne)]diphenol­ato}­copper(II) 
In the title square-planar copper complex, [Cu(C20H22N2O6)], the Cu—N and Cu—O bond lengths are significantly longer than those of its isostructural nickel analog. The title structure is related to that of the corresponding monohydrate. There are significant differences in the conformations of the two complexes. While the monohydrate is mainly planar, in the title compound there is a slight twist in the two benzene rings at each end of the complex [dihedral angle = 13.14 (6)°]. All the atoms of the meth­oxy substitutents are in the plane of the ring to which they are attached (r.m.s. deviation = 0.0079 Å) except for one of the meth­oxy C atoms, which deviates slightly [0.309 (4) Å]. In the crystal, weak C—H⋯O inter­molecular inter­actions link the mol­ecules.
doi:10.1107/S1600536810017137
PMCID: PMC2979637  PMID: 21579299

Results 1-25 (187779)