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1.
Artigo em Inglês | MEDLINE | ID: mdl-38700936

RESUMO

The crystal structures of three mixed-valence copper cyanide alkanolamine polymers are presented, together with thermogravimetric analysis (TGA) and electron spin resonance (ESR) data. In all three structures, a CuII moiety on a crystallographic center of symmetry is coordinated by two alkanolamines and links two CuICN chains via cyanide bridging groups to form diperiodic sheets. The sheets are linked together by cuprophilic CuI-CuI interactions to form a three-dimensional network. In poly[bis(µ-3-aminopropanolato)tetra-µ-cyanido-dicopper(I)dicopper(II)], [Cu4(CN)4(C3H8NO)2]n, 1, propanolamine bases have lost their hydroxyl H atoms and coordinate as chelates to two CuII atoms to form a dimeric CuII moiety bridged by the O atoms of the bases with CuII atoms in square-planar coordination. The ESR spectrum is very broad, indicating exchange between the two CuII centers. In poly[bis(2-aminopropanol)tetra-µ-cyanido-dicopper(I)copper(II)], [Cu3(CN)4(C3H9NO)2]n, 2, and poly[bis(2-aminoethanol)tetra-µ-cyanido-dicopper(I)copper(II)], [Cu3(CN)4(CH7NO)2]n, 3, a single CuII atom links the CuICN chains together via CN bridges. The chelating alkanolamines are not ionized, and the OH groups form rather long bonds in the axial positions of the octahedrally coordinated CuII atoms. The coordination geometries of CuII in 2 and 3 are almost identical, except that the Cu-O distances are longer in 2 than in 3, which may explain their somewhat different ESR spectra. Thermal decomposition in 2 and 3, but not in 1, begins with the loss of HCN(g), and this can be correlated with the presence of OH protons on the ligands in 2 and 3, which are not present in 1.

2.
IUCrdata ; 9(Pt 3): x240189, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38586521

RESUMO

The title compound, C16H17BrO2S, crystallizes as the erythro (RR/SS) isomer of a pair of sulfones that were diastereomeric due to chirality of the α-carbon atoms on the sulfone sulfur atom. The structural analysis was pivotal in showing that the 1,3 elimination reactions of these compounds, which lead to substituted stilbenes, occur with inversion at each asymmetric carbon atom. In the crystal, C-H⋯Br and C-H⋯O hydrogen bonds link the mol-ecules into a tri-periodic inter-molecular network.

3.
Acta Crystallogr E Crystallogr Commun ; 80(Pt 1): 88-93, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38312156

RESUMO

Syntheses of the acyclic amidinium salts, morpholino-formamidinium hexa-fluorido-phosphate [OC4H8N-CH=NH2]PF6 or C5H11N2O+·PF6 -, 1, and pyrrolidinoformamidinium hexa-fluorido-phosphate [C4H8N-CH= NH2]PF6 or C5H11N2 +·PF6 -, 2, were carried out by heating either morpholine or pyrrolidine with triethyl orthoformate and ammonium hexa-fluorido-phosphate. Crystals of 1 obtained directly from the reaction mixture contain one cation and one anion in the asymmetric unit. The structure involves cations linked in chains parallel to the b axis by N-H⋯O hydrogen bonds in space group Pbca, with glide-related chains pointing in opposite directions. Crystals of 1 obtained by recrystallization from ethanol, however, showed a similar unit cell and the same basic structure, but unexpectedly, there was positional disorder [occupancy ratio 0.639 (4):0.361 (4)] in one of the cation chains, which lowered the crystal symmetry to the non-centrosymmetric space group Pca21, with two cations and anions in the asymmetric unit. In the pyrrolidino compound, 2, cations and anions are ordered and are stacked separately, with zigzag N-H⋯F hydrogen-bonding between stacks, forming ribbons parallel to (101), extended along the b-axis direction. Slight differences in the delocalized C=N distances between the two cations may reflect the inductive effect of the oxygen atom in the morpholino compound.

4.
Acta Crystallogr C Struct Chem ; 79(Pt 1): 12-17, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36602016

RESUMO

The title compound, [Al4(CH3)8(C2H7N)2H2], crystallizes as eight-membered rings with -(CH3)2Al-(CH3)2N-(CH3)2Al- moieties connected by single hydride bridges. In the X-ray structure, the ring has a chair conformation, with the hydride H atoms being close to the plane through the four Al atoms. An optimized structure was also calculated by all-electron density functional theory (DFT) methods, which agrees with the X-ray structure but gives a somewhat different geometry for the hydride bridge. Charges on the individual atoms were determined by valence shell occupancy refinements using MoPro and also by DFT calculations analyzed by several different methods. All methods agree in assigning a positive charge to the Al atoms, negative charges to the C, N, and hydride H atoms, and small positive charges to the methyl H atoms.

5.
IUCrdata ; 7(Pt 1): x211351, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36337089

RESUMO

The title compound, C14H12Br2O2S, crystallizes as the meso isomer of a diastereoisomeric pair. This structure determination was key to determining that the 1,3 elimination of bromine by tri-phenyl-phosphine occurs with inversion of the configuration at each of the two chiral carbon atoms. In the crystal, the molecules are linked by weak C-H⋯O and C-H⋯Br hydrogen bonds.

6.
IUCrdata ; 7(Pt 6): x220607, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36339894

RESUMO

The chemical formulation of the title compound was established as trans-[PtCl{P(C2H5)3(CO)}BF4 by single-crystal X-ray analysis, in contrast to the five-coordinate tetra-fluoro-ethyl-ene complex that had been anti-cipated. The compound had been prepared by reaction of trans-PtHCl(P(C2H5)3)2 with C2F4 in the absence of air, and the presence of the carbonyl group was not suspected. The square-planar cations and BF4 - anions are linked by C-H⋯F and C-H⋯O inter-actions into thick wavy (010) sheets. The present crystal-structure refinement is based on the original intensity data recorded in 1967.

7.
Acta Crystallogr C Struct Chem ; 76(Pt 5): 405-411, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32367820

RESUMO

The compound poly[2-hydroxy-N-methylethan-1-aminium [µ3-cyanido-κ3C:C:N-di-µ-cyanido-κ4C:N-dicuprate(I)]], {(C3H10NO)[Cu2(CN)3]}n or [meoenH]Cu2(CN)3, crystallizes in the tetragonal space group P43. The structure consists of a three-dimensional (3D) anionic CuICN network with noncoordinated protonated N-methylethanolamine cations providing charge neutrality. Pairs of cuprophilic Cu atoms are bridged by the C atoms of µ3-cyanide ligands, which link these units into a 43 spiral along the c axis. The spirals are linked together into a 3D anionic network by the two other cyanide groups. The cationic moieties are linked into their own 43 spiral via N-H...O and O-H...O hydrogen bonds, and the cations interact with the 3D network via an unusual pair of N-H...N hydrogen bonds to one of the µ2-cyanide groups. Thermogravimetric analysis indicates an initial loss of the base cation and one cyanide as HCN at temperatures in the range 130-250 °C to form CuCN. We show how loss of a specific cyanide group from the 3D CuCN structure could form the linear CuCN structure. Further heating leaves a residue of elemental copper, isolated as the oxide.

8.
IUCrdata ; 5(Pt 7): x200968, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36339778

RESUMO

The title compound, (C4H12N)[Cu3(CN)4] n , crystallizes as a CuCN network solid, with di-ethyl-ammonium cations sandwiched between planar CuCN sheets comprised of trigonal planar and digonally coordinated CuI atoms bridged by linear CN groups to form 24-membered rings. The digonally coordinated CuI atoms and the di-ethyl-ammonium cations lie on separate crystallographic twofold rotation axes. One of the two independent CN groups has a 50:50 disordered orientation, while the other has one orientation favored due to a N-H⋯NC hydrogen bond between the di-ethyl-ammonium cation and the anionic CuCN framework. These hydrogen bonds link the sheets together into a three-dimensional network.

9.
Acta Crystallogr E Crystallogr Commun ; 75(Pt 3): 332-337, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30867943

RESUMO

The crystal structure of the Ni-14 macrocycle salt, (5,7,7,12,12,14-hexa-methyl-1,4,8,11-tetra-aza-cyclo-tetra-deca-ne)nickel(II) bis-(perchlorate) hemihydrate, [Ni(C16H36N4)]2(ClO4)4·H2O, contains two different diasteriomeric macrocyclic cations in the asymmetric unit, one with two NH protons on each side of the cation (Ia), and the other with all four NH protons on the same side (Ib). The crystal structure of the bromide trihydrate salt of the same Ni-14 macrocyclic cation, namely (5,7,7,12,12,14-hexa-methyl-1,4,8,11-tetra-aza-cyclo-tetra-deca-ne)nickel(II) dibromide trihydrate, [Ni(C16H36N4)]Br2·3H2O (II), contains only the same diastereomer as Ib, with the four N-H bonds on the same side. The geometry around the Ni atom differs slightly between the two diastereomeric cations, as the mean Ni-N distance in Ia is 1.952 (2) Å, while that for Ib and II is 1.928 (2) Å. The hexa-methyl substitution in all three macrocyclic cations has the two dimethyl-substituted C atoms cis to one another, different from the trans 5,5,7,12,12,14-hexa-methyl Ni-14 cations found in all but one of the many published crystal structures of hexa-methyl Ni-14 macrocycles. In each of the two crystal structures, the anions, water mol-ecules, and N-H protons of the macrocyclic cations form extensive hydrogen-bonded zigzag chains propagating along [001] in I and [010] in II.

10.
Acta Crystallogr E Crystallogr Commun ; 74(Pt 9): 1227-1230, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-30225105

RESUMO

In the title compound, [Fe(C11H11N3)2](C10N6), the FeII cation is coordinated by two bis(pyridin-2-yl)methanamine (dipa) ligands and has crystallographic twofold symmetry. There are deviations from ideal octa-hedral geometry due to the steric requirements of the ligands. The polynitrile 1,1,3,3-tetra-cyano-2-(di-cyano-methylid-ene)propane-1,3-diide (tcpd2-) dianion is disordered about an inversion center and is not coordinated to the Fe atom. The anion is not planar but has a propeller shape. In the crystal, weak N-H⋯N inter-actions between the amine H atoms of the dipa ligands and two nitrile groups of the anion form an alternating chain of cations and anions related by the C-centering of the unit cell.

11.
Acta Crystallogr E Crystallogr Commun ; 73(Pt 9): 1357-1362, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28932474

RESUMO

The crystal structures of the trans-fused compound potassium trans-bi-cyclo-[5.1.0]octane-4-carboxyl-ate monohydrate, K+·C9H13O2-·H2O, (I), and of cis-bi-cyclo-[5.1.0]octan-4-yl 4-bromo-benzene-sulfonate, C14H17BrO3S, (II), have been determined. Compound (I) represents the smallest trans-fused cyclo-propane structure known to date, and features the expected shortening of the bridging C-C bond relative to the other cyclo-propane bond lengths, in contrast to the cis-fused system, (II), where all of the cyclo-propane bond lengths are the same. The bicyclic ring system of (I) is disordered across a crystallographic mirror plane. The geometries of the cis-fused and trans-fused ring systems are compared.

12.
Acta Crystallogr E Crystallogr Commun ; 73(Pt 2): 141-146, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-28217329

RESUMO

The crystal structures of two mixed-valence copper cyanide compounds involving N-methyl-ethylenedi-amine (meen), are described. In compound (I), poly[bis(µ3-cyanido-κ3C:C:N)tris(µ2-cyanido-κ2C:N)bis(N-methylethane-1,2-di-amine-κ2N,N')tricopper(I)copper(II)], [Cu4(CN)5(C3H10N2)2] or Cu4(CN)5meen2, cyanide groups link CuI atoms into a three-dimensional network containing open channels parallel to the b axis. In the network, two tetra-hedrally bound CuI atoms are bonded by the C atoms of two end-on bridging CN groups to form Cu2(CN)6 moieties with the Cu atoms in close contact at 2.560 (1) Å. Other trigonally bound CuI atoms link these units together to form the network. The CuII atoms, coordinated by two meen units, are covalently linked to the network via a cyanide bridge, and project into the open network channels. In the mol-ecular compound (II), [(N-methylethylenediamine-κ2N,N')copper(II)]-µ2-cyanido-κ2C:N-[bis(cyanido-κC)copper(I)] monohydrate, [Cu2(CN)3(C3H10N2)2]·H2O or Cu2(CN)3meen2·H2O, a CN group connects a CuII atom coordinated by two meen groups with a trigonal-planar CuI atom coordinated by CN groups. The mol-ecules are linked into centrosymmetric dimers via hydrogen bonds to two water mol-ecules. In both compounds, the bridging cyanide between the CuII and CuI atoms has the N atom bonded to CuII and the C atom bonded to CuI, and the CuII atoms are in a square-pyramidal coordination.

13.
Acta Crystallogr E Crystallogr Commun ; 72(Pt 7): 892-6, 2016 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-27555925

RESUMO

In the title compound, {(C6H16NO)[Cu2(CN)3]} n , the cyanide groups link the Cu(I) atoms into an open three-dimensional anionic network, with the mol-ecular formula Cu2(CN)3 (-). One Cu(I) atom is tetra-hedrally bound to four CN groups, and the other Cu(I) atom is bonded to three CN groups in an approximate trigonal-planar coordination. The tetra-hedrally coordinated Cu(I) atoms are linked into centrosymmetric dimers by the C atoms of two end-on bridging CN groups which bring the Cu(I) atoms into close contact at 2.5171 (7) Å. Two of the cyanide groups bonded to the Cu(I) atoms with trigonal-planar surrounding link the dimeric units into columns along the a axis, and the third links the columns together to form the network. The N,N-di-ethyl-ethano-lamine mol-ecules used in the synthesis have become protonated at the N atoms and are situated in cavities in the network, providing charge neutrality, with no covalent inter-actions between the cations and the anionic network.

14.
Acta Crystallogr E Crystallogr Commun ; 71(Pt 10): m181-2, 2015 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-26594426

RESUMO

The title compound, [Au(C18H10F4PS)Cl2], crystallizes as neutral mol-ecules, with the Au(III) atom coordinated by two Cl atoms and by the P and S atoms of the bidentate phosphanyl thiol-ate ligand, in a slightly distorted square-planar environment. The mol-ecules are linked into centrosymmetric dimers via long axial Au-Cl bonds of 3.393 (4) Å. This axial Au-Cl distance is longer than is usually seen, although one other example has been given. Dimer formation may explain the unexpectedly low solubility of the compound in common polar solvents. There is also a separate inter-molecular Au-F contact of 3.561 (6) Å, but this distance seems too long to be regarded as a bond. Two putative C-H⋯F hydrogen bonds appear to link the dimers into sheets parallel to (110). There is a short inter-molecular F⋯F contact of 2.695 (10) Šbetween two dimers related by the twofold axis.

15.
Acta Crystallogr E Crystallogr Commun ; 71(Pt 11): 1278-82, 2015 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-26594491

RESUMO

The title compound, C30H28O2, was obtained during recrystallization of (±)-1,2-diphenyl-1,2-propane-diol in 1-butanol, from an unexpected non-acid-catalyzed pinacol rearrangement followed by acetal formation of the newly formed aldehyde with the diol. The tri-substituted dioxolane ring has a twist conformation on the C-O bond opposite the methyl-substituted C atom. There is an intra-molecular C-H⋯π inter-action present involving one of the di-phenyl-ethyl rings and an H atom of the phenyl ring in position 4 of the dioxolane ring. In the crystal, mol-ecules are linked by weak C-H⋯O hydrogen bonds, forming chains along [001]. The chains are linked by a second C-H⋯π inter-action, forming sheets parallel to the bc plane.

16.
Acta Crystallogr E Crystallogr Commun ; 71(Pt 6): 716-9, 2015 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-26090159

RESUMO

In the title compound, [Cu(C4H12P2S2)2]BF4, both diphosphine di-sulfide mol-ecules bind to the Cu(I) atom, as chelating ligands via the S atoms, forming a monovalent cation with a slightly distorted tetra-hedral coordination around the Cu(I) atom. The average Cu-S distance is 2.350 (15) Å, with small but possibly significant differences within each chelate ring. Ligand P=S distances average 1.964 (3) Å, and the P-P distances are 2.2262 (13) and 2.2166 (14) Å. The ligand chelate rings are twisted in opposite directions, with one in the λ and one in the δ configuration. Although the anisotropic displacement parameters of the F atoms of the anion are quite large compared to that of the B atom, difference Fourier syntheses indicate only one set of sites for the F atoms. In the crystal, possible C-H⋯F hydrogen bonds may stabilize the orientation. The B-F distances, uncorrected for libration, average 1.359 (6) Å.

17.
Acta Crystallogr Sect E Struct Rep Online ; 70(Pt 11): 281-5, 2014 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-25484723

RESUMO

In the title compound, [Cu(NCS)(C3H9PS)] n , the thio-cyanate ions bind the Cu(I) atoms covalently, forming infinite -Cu-SCN-Cu- chains parallel to the a axis. Each Cu(I) atom is also coordinated to a tri-methyl-phosphine sulfide group via a Cu-S bond. Two crystallographically independent chains propagate in opposite directions, and are held together in a ribbon arrangement by long bonds between Cu(I) atoms in the first chain and thio-cyanate S atoms in the second, with Cu-S = 2.621 (1) Å. The geometry around the Cu(I) atoms in the first chain is distorted tetra-hedral, with angles involving the long Cu-S bond much less than ideal, and the S-Cu-N angle between the phosphine sulfide S atom and the thio-cyanate N atom opening out to 133.19 (9)°. Each Cu(I) atom in the second chain appears to be disordered between two positions 0.524 (4) Šapart, with occupancy factors of 0.647 (6) and 0.353 (6). The Cu(I) atom in the major site is in a distorted trigonal-planar configuration, with the S-Cu-N angle between the phosphine sulfide and the thio-cyanate N atom again opened out, to 137.01 (15)°. The Cu(I) atom in the minor site, however, forms in addition a long bond [Cu-S = 2.702 (5) Å] to the phosphine sulfide of the first chain, not the thio-cyanate S atom, to provide a further link between the chains.

18.
Acta Crystallogr Sect E Struct Rep Online ; 70(Pt 7): m254, 2014 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-25161520

RESUMO

In the title compound, [µ-(2,6,7-η:3,4,5-η)-cycloocta-2,4,6-trienone]bis-(tri-carbonyl-iron)(Fe-Fe), [Fe2(C8H8O)(CO)6], the diiron hexa-carbonyl moiety has a sawhorse arrangement, with the OC-Fe-Fe-CO fragment forming the horizontal bar of the horse, and the other four carbonyl groups the legs. The Fe-Fe distance is 2.795 (2) Å. Each Fe atom is also bonded to three C atoms of the cyclo-octa-trienone ring. One Fe atom forms a σ-bond with one ring C atom, with Fe-C = 2.109 (2) Å, and also a metal-olefin π-bond with two C atoms on the other side of the ring, with Fe-C distances of 2.238 (2) and 2.236 (3) Å. The second Fe atom forms a η(3)-allyl bond with three other ring atoms, with Fe-C bond lengths of 2.158 (2), 2.062 (2), and 2.123 (3) Å. Counting the π- and π-allyl inter-actions as one bond, the coordinations of the Fe atoms can, respectively, be approximated as octa-hedral and trigonal bipyramidal.

19.
Acta Crystallogr Sect E Struct Rep Online ; 70(Pt 4): o400-1, 2014 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-24826119

RESUMO

In the title compound, C22H32O4, the atoms of the methyl ester group and the alk-oxy O atoms are all coplanar with the central aromatic ring, with an r.m.s. deviation of 0.008 Å. Bonds to the methyl-ene and cyclo-hexyl groups are also very close to this plane, so that the mol-ecule is essentially flat, apart from the cyclo-hexyl groups. The mean planes through the cyclo-hexyl groups are tilted by 30.08 (9) and 36.14 (7)° with respect to the central aromatic ring. In the crystal, pairs of mol-ecules linked by C-H⋯O hydrogen bonds form planar units which are stacked along the a axis, with an average inter-planar distance of 3.549 (2) Å. Stacking appears to be stabilized by further weak C-H⋯O hydrogen bonds.

20.
Acta Crystallogr Sect E Struct Rep Online ; 70(Pt 2): m76-7, 2014 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-24764834

RESUMO

In the title complex, [Cu(I)Cu(II)(CN)3(C4H12N2)2], the Cu(I) and Cu(II) ions and a bridging cyanide group lie on a twofold rotation axis. The Cu(II) ion is in a slightly-distorted square-pyramidal coordination environment, with the N atoms of the two symmetry-related N-ethyl-ethylenedi-amine ligands occupying the basal positions and an N-bonded cyanide group in the apical position. The Cu(I) ion is in a trigonal-planar coordination environment, bonded to the C atom of the bridging cyanide group and to two terminal cyanide groups. In the crystal, N-H⋯N hydrogen bonds involving two of the symmetry-unique N-H groups of the N-ethyl-ethylenedi-amine ligands and the N atoms of the terminal cyanide ligands link the mol-ecules into strands along [010].

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