Search tips
Search criteria

Results 1-25 (4427)

Clipboard (0)
Year of Publication
1.  Lotharmeyerite, Ca(Zn,Mn)2(AsO4)2(H2O,OH)2  
Lotharmeyerite, calcium bis­(zinc/manganese) bis­(arsenate) bis­(hydroxide/hydrate), Ca(Zn,Mn3+)2(AsO4)2(H2O,OH)2, is a member of the natrochalcite group of minerals, which are characterized by the general formula AM 2(XO4)2(H2O,OH)2, where A may be occupied by Pb2+, Ca2+, Na+, and Bi3+, M by Fe3+, Mn3+, Cu2+, Zn2+, Co2+, Ni2+, Al3+, and Mg2+, and X by PV, AsV, VV, and SVI. The minerals in the group display either monoclinic or triclinic symmetry, depending on the ordering of chemical components in the M site. Based on single-crystal X-ray diffraction data of a sample from the type locality, Mapimi, Durango, Mexico, this study presents the first structure determination of lotharmeyerite. Lotharmeyerite is isostructural with natrochalcite and tsumcorite. The structure is composed of rutile-type chains of edge-shared MO6 octa­hedra (site symmetry ) extending along [010], which are inter­connected by XO4 tetra­hedra (site symmetry 2) and hydrogen bonds to form [M 2(XO4)2(OH,H2O)2] sheets parallel to (001). These sheets are linked by the larger A cations (site symmetry 2/m), as well as by hydrogen bonds. Bond-valence sums for the M cation, calculated with the parameters for Mn3+ and Mn2+ are 2.72 and 2.94 v.u., respectively, consistent with the occupation of the M site by Mn3+. Two distinct hydrogen bonds are present, one with O⋯O = 2.610 (4) Å and the other O⋯O = 2.595 (3) Å. One of the H-atom positions is disordered over two sites with 50% occupancy, in agreement with observations for other natrochalcite-type minerals, such as natrochalcite and tsumcorite.
PMCID: PMC3254273  PMID: 22259316
2.  (2,2′-Bipyridine-4,4′-dicarb­oxy­lic acid-κ2 N,N′)chlorido(2,2′:6′,2′′-terpyridyl-κ3 N,N′,N′′)ruthenium(II) perchlorate ethanol monosolvate monohydrate 
In the title compound, [RuCl(C15H11N3)(C12H8N2O4)]ClO4·C2H5OH·H2O, the geometry of the ClN5 coordination set around the RuII atom is close to octa­hedral, but distorted on account of the limited bite angles of the polypyridyl ligands. The complexes are linked by O—H⋯O hydrogen bonds between the carboxyl groups and the crystal lattice water mol­ecules into chains along [110]. Face-to-face stacking inter­actions are formed between terpyridine ligands, with inter­planar separations of 3.66 (1) and 3.42 (1) Å, and between bipyridine-4,4′-dicarb­oxy­lic acid ligands, with inter­planar separations of 3.65 (1) and 3.72 (1) Å. Three O atoms of the perchlorate ion are each disordered equally over two positions. The hy­droxy group of the ethanol mol­ecule is also disordered over two sites with refined occupancies of 0.794 (9) and 0.206 (9).
PMCID: PMC3254339  PMID: 22259372
3.  Di-n-butyl­bis­(N-ethyl-N-phenyl­dithio­carbamato-κS)tin(IV) 
The title compound, [Sn(C4H9)2(C9H10NS2)2], features a tetra­hedrally coordinated SnIV atom; the dithio­carbamate ligands coordinate in a monodentate fashion, accompanied by two n-butyl chains. The non-coordinating thione S atoms are each proximate to the SnIV atom [3.0136 (7) and 2.9865 (8) Å], giving rise to distortions from the ideal geometry as evident in the wide C—Sn—C bond angle of 139.06 (12) °. In the crystal, C—H⋯S inter­actions lead to the formation of a linear supra­molecular chain along the b axis. The chains are aligned into layers by C—H⋯π inter­actions, and the layers stack along [001]. One of the ethyl groups is statistically disordered over two sets of sites.
PMCID: PMC3254340  PMID: 22259373
4.  Bis[μ-N-(diethyl­amino-κN)dimethyl­silylanilido-κ2 N:N]bis­[chlorido­cobalt(II)] 
In the title binuclear CoII complex, [Co2(C12H21N2Si)2Cl2], an inversion center is located at the mid-point between the two Co atoms in the dimeric mol­ecule. The bidentate N-silylated anilide ligand coordinates the CoII atom in an N,N′-chelating mode and provides the anilide N atom as a bridge to link two CoII atoms. The two ends of the N—Si—N chelating unit exhibit different affinities for the metal atom. The Co—Nanilide bond is 2.031 (6) Å and Co—Namino bond is 2.214 (6) Å. The four-coordinate Co atom presents a distorted tetra­hedral geometry, while the dimeric aggregation exhibits a (CoN)2 rhombus core with 1.998 (6) Å as the shortest sides and shows a ladder structure composed of Co, N and Si atoms.
PMCID: PMC3254341  PMID: 22259375
5.  {4,4′-Dimethyl-2,2′-[(2,2-dimethyl­propane-1,3-di­yl)bis­(nitrilo­methanylyl­idene)]diphenolato}nickel(II) monohydrate 
In the title compound, [Ni(C21H24N2O2)]·H2O, both the complex mol­ecule and the water mol­ecule lie on a twofold rotation axis. The NiII ion is coordinated in a distorted square-planar geometry by the tetra­dentate ligand. The dihedral angle between the two symmetry-related benzene rings is 47.12 (8)°. In the crystal, pairs of symmetry-related O—H⋯O hydrogen bonds form R 2 2(6) ring motifs. In addition, there are weak inter­molecular C—H⋯O hydrogen bonds, and π–π stacking inter­actions with a centroid–centroid distance of 3.4760 (8) Å.
PMCID: PMC3254342  PMID: 22259376
6.  Bis(4-fluoro­benz­yl)bis­(4-phenyl-5-sulfanyl­idene-4,5-dihydro-1,3,4-thio­diazole-2-thiol­ato)tin(IV) 
In the title complex, [Sn(C7H6F)2(C8H5N2S3)2], including the weak Sn—N inter­actions, the SnIV atom is situated in a distorted trans-octa­hedral geometry, and the equatorial plane is defined by two chelating 4-phenyl-5-sulfanyl­idene-4,5-dihydro-1,3,4-thio­diazole-2-thiol­ate ligands. The apical positions are occupied by two C atoms of 4-fluoro­benzyl groups.
PMCID: PMC3254343  PMID: 22259377
7.  Poly[(2,2′-bipyridine-κ2 N,N′)(μ3-2,4,6-trimethyl­isophthalato-κ5 O 1,O 1′:O 1:O 3,O 3′)cadmium] 
In the crystal structure of the polymeric title complex, [Cd(C11H10O4)(C10H8N2)]n, the CdII cation is chelated by one 2,2-bipyridine ligand and two carboxyl groups from two trimethyl­isophthalate (TMIPA) anions, and is further coordinated by one carboxyl­ate O atom from a third TMIPA anion, forming a distorted penta­gonal–bipyramidal geometry. Each TMIPA anion bridges three CdII cations, forming polymeric complex sheets parallel to (001). Weak C—H⋯O hydrogen bonding occurs between adjacent sheets.
PMCID: PMC3254344  PMID: 22259378
8.  {N′-[(2-Oxidonaphthalen-1-yl)methyl­idene]benzohydrazidato}(1,10-phenanthroline)copper(II) methanol monosolvate 
The title mononuclear complex, [Cu(C18H12N2O2)(C12H8N2)]·CH3OH, contains one N′-[(2-oxidonaphthalen-1-yl)methyl­idene]benzohydrazidate ligand (L 2−), a Cu2+ cation, one 1,10-phenanthroline ligand and a methanol solvent mol­ecule. The CuII ion adopts a CuO2N3 distorted square-pyramidal coordination. An O—H⋯O hydrogen bond is formed between the methanol solvent mol­ecule and the hydrazide O atom of the L 2− ligand.
PMCID: PMC3254345  PMID: 22259379
9.  Bis(μ-trimethyl­silanolato-κ2 O:O)bis­{[2-(2H-benzotriazol-2-yl)-4,6-di-tert-pentyl­phenolato-κ2 N,O]zinc} 
The binuclear title complex, [Zn2(C22H28N3O)2(C3H9OSi)2], has a crystallographic imposed centre of symmetry. The ZnII atom is coordinated by three O and one N atom from one 2-(2H-benzotriazol-2-yl)-4,6-di-tert-pentyl­phenolate ligand and two bridging trimethyl­silanolate anions in a distorted tetra­hedral geometry. The dihedral angle between the benzotriazole ring system and the benzene ring is 19.83 (5)°. The tert-pentyl groups are disordered over two orientations with refined site-occupancy ratios of 0.858 (4):0.142 (4) and 0.665 (6):0.335 (6).
PMCID: PMC3254346  PMID: 22259380
10.  Bis(μ-pyridinium-2-carboxyl­ato-κ2 O:O′)bis­[triaqua­(sulfato-κO)manganese(II)] 
The asymmetric unit of the title compound, [Mn2(SO4)2(C6H5NO2)2(H2O)6], comprises half of a centrosymmetric dimer. The MnII atom is coordinated by two O atoms of the monodentate carboxyl­ate ligand, an O atom of the sulfate anion in axial position and three water mol­ecules in a distorted octa­hedral geometry. In the crystal, mol­ecules are connected through N—H⋯O and O—H⋯O hydrogen bonds, forming a three-dimensional network. The crystal structure is further stabilized by inter­molecular π–π inter­actions [centroid–centroid distance = 3.842 (2) Å].
PMCID: PMC3254347  PMID: 22259381
11.  cis-Bis(4-methyl­piperazine-1-carbo­dithio­ato-κ2 S,S′)bis­(pyridine-κN)cadmium 
In the title complex, [Cd(C6H11N2S2)2(C5H5N)2], the CdII ion is hexa­coordinated by two N atoms from two pyridine ligands and by four S atoms from two dithio­carbamate ligands in a distorted octa­hedral geometry. The CdII ion lies on a twofold axis. The piperazine ring is in chair conformation and its least-squares plane makes a dihedral angle of 81.4 (1)° with that of the pyridine ring.
PMCID: PMC3254348  PMID: 22259382
12.  Tetra­hedral zinc in tetra­kis­(1-methyl-1H-imidazole-κN 3)zinc bis­(tetra­fluorido­borate) 
In the title compound, [Zn(C4H6N2)4](BF4)2, the ZnII ion is in a slightly distorted tetra­hedral coordination geometry, with Zn—N distances in the range 1.980 (2)–1.991 (2) Å. The tetra­hedral angles are in the range 104.93 (9)–118.81 (9)°.
PMCID: PMC3254349  PMID: 22259384
13.  catena-Poly[[bis­(acetato-κO)aqua­copper(II)]-μ-5-(pyridin-3-yl)pyrimidine-κ2 N 1:N 5] 
In the title compound, [Cu(CH3CO2)2(C9H7N3)(H2O)]n, the CuII ion is penta­coordinated in a square-pyramidal geometry. The N atoms of the two chelating symmetry-related 5-(pyridin-3-yl)pyrimidine ligands and the O atoms of the two monodentate acetate anions are nearly coplanar, with a mean deviation from the least-squares plane of 0.157 (2) Å and the CuII ion is displaced by 0.050 (3) Å from this plane towards the apical water O atom. Bridging through the bis-monodentate 5-(pyridin-3-yl)pyrimidine ligand forms a one-dimensional coordination polymer extending parallel to [010]. In the crystal, O—H⋯O hydrogen bonds link the mol­ecules into a two-dimensional supra­molecular structure parallel to (100). The crystal studied was an inversion twin with a 0.57 (3):0.43 (3) domain ratio.
PMCID: PMC3254350  PMID: 22259385
14.  Chlorido{2-[(dimethyl­amino)­meth­yl]phenyl-κ2 N,C 1}tellurium 
The crystal structure of the title compound, C9H12ClNTe, contains isolated mol­ecules with no close Te⋯Cl inter­molecular contacts and has the same composition as a previously published structure [Engman et al. (2004 ▶). Phospho­rus Sulfur Silicon Relat. Elem. 179, 285–292]. However, in this case, the compound has crystallized in a centrosymmetric space group, unlike the previously published structure which contained enanti­omerically pure chiral mol­ecules. In all other aspects, the metrical parameters are similar. The mol­ecules with a T-shaped coordination environment about the Te atom are linked into dimers by C—H⋯Cl inter­actions.
PMCID: PMC3254548  PMID: 22259496
15.  Dibromidochlorido{2-[(dimethyl­amino)­meth­yl]phenyl-κ2 N,C 1}tellurium(IV) 
The title compound, C9H13Br2ClNTe, was synthesized by reacting [2-(dimethyl­amino­meth­yl)phen­yl]tellurium(II) chlor­ide with Br2. As a consequence, the Cl and Br atoms are not well ordered but distributed over the three possible positions such that the overall stiochiometry is two Br atoms and one Cl atom. The scrambling of the Br and Cl atoms indicates a small energy barrier for the exchange process between the apical and equatorial positions. Overall, the Te atom geometry is slightly distorted square pyramidal (τ = 0.052 for the major component). However, there is a weak secondary inter­action between the Te atoms and the disordered Br/Cl atoms of a nearby mol­ecule. The Te—Br and Te—Cl distances in both disorder components fall into two groups; a longer distance for the Br/Cl involved in this secondary inter­action [2.6945 (17) Å for Br and 2.601 (9)Å for Cl] and shorter bond distances to the remaining halogen atoms, indicating that this inter­action has slightly weakened the Te—X bond, as is the case in the previously reported tribromido structure [Singh et al. (1990). J. Chem. Soc. Dalton Trans. pp. 907–913]. Otherwise, the metrical parameters in the two structures are not significantly different. An intermolecular C—H⋯Br interaction occurs.
PMCID: PMC3254549  PMID: 22259497
16.  Methyl 2-{[2-(4,4,5,5-tetra­methyl-1,3-dioxyl-4,5-dihydro­imidazol-2-yl)phen­yl]­oxy}acetate 
In the title compound, C16H21N2O5, the benzene ring is nearly perpendicular to the imidazole ring, making a torsion angle of 88.6 (8)°·The crystal structure is stabilized by non-classical C—H⋯O and C—H⋯π inter­actions, which build up a three-dimensional network.
PMCID: PMC3254550  PMID: 22259498
17.  2-[3-Hy­droxy-4-(2-hy­droxy­eth­oxy)phen­yl]-4,4,5,5-tetra­methyl-2-imidazoline-1-oxyl 3-oxide 
In the title compound, C15H21N2O5, the imidazoline ring displays a twisted conformation. The mean plane of the imidazoline ring makes a dihedral angle of 22.55 (5)° with the benzene ring. In the crystal, O—H⋯O and C—H⋯O hydrogen bonds link the mol­ecules into a layer parallel to the bc plane.
PMCID: PMC3254551  PMID: 22259499
18.  4-Chloro-1-methyl­indoline-2,3-dione 
The title mol­ecule, C9H6ClNO2, is essentially planar; the maximum deviation of the indoline ring system is 0.027 (3) Å and the substituents do not deviate by more than 0.075 (2) Å from this plane. Inter­molecular C—H⋯O hydrogen bonds consolidate the crystal structure.
PMCID: PMC3254552  PMID: 22259500
19.  (E)-4-[(3,5-Dimethyl­phen­yl)imino­meth­yl]-2-meth­oxy-3-nitro­phenol 
The mol­ecule of the title compound, C16H16N2O4, exists in the E configuration with respect to the central C=N double bond. The dihedral angle between the two benzene rings is 2.17 (9) Å. In the crystal, mol­ecules are linked via O—H⋯N hydrogen bonds into chains that propagate along the b-axis direction. There is also π–π stacking of inversion-related mol­ecules, with inter­planar spacings of 3.479 (5) Å and ring centroid–centroid distances of 3.876 (4) Å.
PMCID: PMC3254553  PMID: 22259502
20.  N-(2-Chloro-5-methyl­phen­yl)succinamic acid 
In the title compound, C11H12ClNO3, the conformation of the N—H bond in the amide segment is syn with respect to the ortho-Cl atom. The amide and carboxyl C=O groups are syn to each other. Furthermore, the C=O and O—H bonds of the carboxyl group are in syn positions with respect to each other. The dihedral angle between the benzene ring and the amide group is 47.8 (2)°. In the crystal, mol­ecules are connected by pairs of O—H⋯O hydrogen bonds, forming inversion dimers. The dimers are further linked by N—H⋯O hydrogen bonds into double chains along the b-axis direction.
PMCID: PMC3254554  PMID: 22259503
21.  4-(2,2-Difluoro-1,3-benzodioxol-4-yl)-1H-pyrrole-3-carbonitrile 
In the title compound, C12H6F2N2O2, the 2,2-difluoro-1,3-benzodioxole ring system is approximately planar [maximum deviation = 0.012 (2) Å] and its mean plane is twisted with respect to the pyrrole ring, making a dihedral angle of 2.51 (9)°. In the crystal, N—H⋯N hydrogen bonds link the mol­ecules into chains running along the a axis. π–π stacking is also observed between parallel benzene rings of adjacent mol­ecules, the centroid–centroid distance being 3.7527 (13) Å.
PMCID: PMC3254555  PMID: 22259504
22.  Ethane-1,2-diaminium (R)-2-[4-(1-carboxyl­atoeth­oxy)phen­oxy]acetate 
In the title compound, C2H10N2 2+·C11H10O6 2−, the two acetate groups of the cation form dihedral angles of 74.2 (4) and 63.9 (5)° with the central benzene ring. In the crystal, N—H⋯O hydrogen bonds link the cations and anions into layers parallel to the ab plane.
PMCID: PMC3254556  PMID: 22259505
23.  N-(5-Sulfanyl­idene-4,5-dihydro-1,3,4-thia­diazol-2-yl)acetamide dimethyl sulfoxide disolvate 
In the title compound, C4H5N3OS2·2C2H6OS, the five-membered heterocyclic ring and the N—(C=O)—C plane of the acetamide group are essentially co-planar, with a dihedral angle of 1.25 (3)°. Inter­molecular N—H⋯O hydrogen bonds between the acetamide compound and the dimethyl sulfoxide mol­ecules stabilize the crystal structure. The two dimethyl sulfoxide mol­ecules are each disordered over two positions with occupancy ratios of 0.605 (2):0.395 (2) and 0.8629 (18):0.1371 (18).
PMCID: PMC3254557  PMID: 22259506
24.  Methyl­ammonium tetra­fluoridoborate 18-crown-6 clathrate 
In the title compound, CH3NH3 +·BF4 −·C12H24O6, the methyl­ammonium cation makes three N—H⋯O hydrogen bonds to the 18-crown-6 mol­ecule. The –NH3 + and –CH3 groups of the cation adopt a staggered conformation. The F atoms of the tetra­fluoridoborate anion are disordered over two sets of sites in a 0.519 (11):0.481 (11) ratio. Weak C—H⋯F inter­actions occur in the crystal, which possibly correlate with the anion disorder.
PMCID: PMC3254558  PMID: 22259507
25.  N-(4,6-Dimeth­oxy­pyrimidin-2-yl)-2-(3-methyl­phen­yl)acetamide 
In the title compound, C15H17N3O3, the dihedral angle between the pyrimidine and benzene rings is 87.0 (7)°. In the crystal, mol­ecules are linked into inversion dimers with R 2 2(8) graph-set motifs by a pair of N—H⋯O hydrogen bonds. Weak C—H⋯O hydrogen bonds and inter­molecular π–π inter­actions [centroid–centroid distance = 3.544 (1) Å] are also observed.
PMCID: PMC3254559  PMID: 22259508

Results 1-25 (4427)