The Crystal and Molecular-Structure of Two Complexes of Cobalt(III) With Pentaaza Macrocyclic Ligands Chloro (1,4,7,10,14-pentaazacycloheptadecane)cobalt(III) Bromide Chloride Hydrate [Co(C12H29N5)Cl] (Br0.33Cl1.67)H2O and Bromo(1,4,7,11,15-pentaazacyclooctadecane)cobalt(III) Bromide [Co(C13H31N5)Br]Br2

1987 ◽  
Vol 40 (5) ◽  
pp. 829 ◽  
Author(s):  
NF Curtis ◽  
GJ Gainsford ◽  
P Osvath ◽  
DC Weatherburn
Keyword(s):  
Chelate Ring ◽  
Octahedral Geometry ◽  
Distorted Octahedral Geometry ◽  
Boat Conformation ◽  
Orthorhombic Space Group ◽  
Space Group ◽  
Membered Chelate Ring ◽  
Ligand Interactions ◽  
Chloride Hydrate ◽  
Chelate Rings

The structures of the compounds chloro (1,4,7,10,14-pentaazacycloheptadecane) cobalt(III) bromide chloride hydrate, [Co( chad )Cl] ( Br0.33Cl1.67)H2O(1) and bromo (1,4,7,11,15-pentaazacyclooctadecane) cobalt(III) bromide, [Co( coad )Br]Br2(2),have been determined by X-ray diffractometry. [Compound (1) orthorhombic, space group P bac, a 1208.5, b 2305.5, c 1318.9 pm, Z 8, R 0.056, Rw 0.071 for 1943 reflections. Compound (2), triclinic, space group P1, a 930.8, b 953.5, c 1120.3pm, α 84.60,β 398.82, γ 105.26�, Z 2, R 0.045, RW0.054 for 4821 reflections.] The compounds have structures with two ( chad ) or three ( coad ) six-membered chelate rings in the equatorial (N4) plane, but with different configurations of the chiral nitrogen centres ; chad : 1SR , 4SR, 7RS, 10RS, that is, with only the NH group at the junction of the two six-membered chelate rings on the same side of the N4 plane as the axial nitrogen; coad : 1 RS, 7SR, 11 SR, 15RS, that is, with NH groups of the central six-membered chelate ring on the same side of the N4 plane as the axial nitrogen, and the others on the opposite side. The chad compound has regular octahedral geometry, with one chair and one boat conformation six-membered chelate ring. The coad compound has distorted octahedral geometry, with long Co-N distances in the N4 plane, attributed to intra-ligand interactions.

The Dichloroplatinum(II) and Dichloropalladium(II) Complexes of 1,4-Diazacycloheptane: Preparative, Structural and Conformational Studies

1996 ◽  
Vol 49 (12) ◽  
pp. 1301 ◽  
Author(s):  
GW Allen ◽  
ECH Ling ◽  
LV Krippner ◽  
TW Hambley
Keyword(s):  
Crystal Structures ◽  
Chelate Ring ◽  
Chair Conformation ◽  
Monoclinic Space Group ◽  
Boat Conformation ◽  
X Ray Diffraction ◽  
Orthorhombic Space Group ◽  
Space Group ◽  
Membered Chelate Ring ◽  
Alternative Conformation

The preparation and purification of [Pt( hpip )Cl2] and [Pd( hpip )Cl2] ( hpip = homopiperazine = 1,4-diazacycloheptane) are described. Crystal structures of [Pt( hpip )Cl2] and [Pd( hpip )Cl2] have been determined by X-ray diffraction methods and refined to R values of 0.023 (932 F) and 0.023 (948 F). The crystals of [Pt( hpip )Cl2] are orthorhombic, space group Pbcm , a 7.7019(8), b 9.8080(12), c 12.1944(14) Ǻ, and those of [Pd( hpip )Cl2] are monoclinic, space group P21/m, a 6.1001(9), b 11.527(2), c 6.458(I) Ǻ, β 106.30(2)°. The seven- membered rings of the ligands in both complexes adopt boat-like conformations in which the five- membered chelate ring has an eclipsed N-C-C-N group and the six- membered chelate ring adopts a chair conformation. Molecular mechanics methods were used to investigate whether this conformation was a crystallographic artefact but it was found to be real. An alternative conformation in which the six-membered chelate ring adopts a skew-boat conformation was also investigated. It was found to be less stable than the conformation observed in the crystal structures, but to a degree that depends on whether non-bonded interactions involving the metal atom were included or not.

scholarly journals Crystal structure of the coordination compound of triiodidomethyltin(IV) with 2,2′-bipyridine, MeSnI3·bipy

2016 ◽  
Vol 72 (1) ◽  
pp. 17-20
Author(s):  
Hans Reuter ◽  
Martin Reichelt
Keyword(s):  
Chelate Ring ◽  
Octahedral Geometry ◽  
Distorted Octahedral Geometry ◽  
Orthorhombic Space Group ◽  
Methyl Group ◽  
Bond Lengths ◽  
Distorted Octahedral ◽  
Bipyridine Ligand ◽  
Twisting Angle ◽  
Van Der Waals Contacts

The title compound, (2,2′-bipyridine-κ2N,N′)triiodidomethyltin(IV), [Sn(CH3)I3(C10H8N2)], crystallizing in the non-centrosymmetric orthorhombic space groupPca21as an inversion twin, represents one of the few structurally characterized coordination compounds of an organotin(IV) trihalide with 2,2′-biypridine. Its distorted octahedral geometry shows a meridional arrangement of the I atoms and the methyl group is in-plane with the five-membered chelate ring. Asymmetric bonding of the biypridine ligand to the tin(IV) atom is reflected by different Sn—N bond lengths [2.268 (4) Åversus2.293 (4) Å] and caused by the statictranseffect of the methyl group. Sn—I bond lengths show some differences with respect to their orientation to the methyl group or the bipyridine ligand, respectively. Angular distortions in the coordination sphere of the SnIVatom mainly arise from the large I atoms. Distortion of the 2,2′-bipyridine ligand as a result of its coordination to the SnIVatom are described by the twisting angle of 2.5 (2)° between the least-squares planes of the two pyridine rings, as well as by the angle of 6.2 (2)° between the two lines through the pyridine-connecting C atoms and thepara-orientated C atoms. Directional intermolecular interactions are restricted to weak I...H van der Waals contacts.

The X-Ray Crystal Structure of 1,2-3,4-Di-O-isopropylidene-4-C-methylthiomethoxy-β-L-arabino-hexoseptanos-5-ulose

1990 ◽  
Vol 43 (12) ◽  
pp. 2083 ◽  
Author(s):  
DC Craig ◽  
VJ James ◽  
JD Stevens
Keyword(s):  
Crystal Structure ◽  
Title Compound ◽  
Membered Ring ◽  
Boat Conformation ◽  
X Ray Diffraction ◽  
Orthorhombic Space Group ◽  
Space Group ◽  
X Ray

The crystal structure of the title compound (1) has been determined by X-ray diffraction. Crystals of (1) are orthorhombic, space group P21212 with a 11.425(1), b 24.916(1), c 5.8952(3)Ǻ, Z 4. Refinement on 1675 observed reflections measured with Cu Kα radiation converged at R 0.034. The seven- membered ring adopts a boat conformation in which the pseudo plane of symmetry passes through the ring oxygen.

Isomers of 1,4,8,11-Tetraazacyclotetradecane-6,13-dicarboxylate Characterized as Cobalt(III) Complexes

2003 ◽  
Vol 56 (7) ◽  
pp. 679 ◽  
Author(s):  
Paul V. Bernhardt ◽  
Trevor W. Hambley ◽  
Geoffrey A. Lawrance ◽  
Marcel Maeder ◽  
Eric N. Wilkes
Keyword(s):  
Physical Properties ◽  
Octahedral Geometry ◽  
Trans Isomers ◽  
Space Group ◽  
Cell Parameters ◽  
Limited Distortion ◽  
Chelate Rings

The major trans (1) and minor cis (2) isomers of 1,4,8,11-tetraazacyclotetradecane-6,13-dicarboxylate have been characterized as the complexes [Co(1)](ClO4) and [Co(H2)(OH2)]Cl(ClO4)·H2O. The former crystallized in the C2/c space group and the latter in the P21/c space group, with cell parameters a 16.258(7), b 9.050(3), c 15.413(6) Å, β133.29(3)°, and a 9.694(4), b 16.135(1), c 12.973(5) Å, β 93.00(2)°, respectively. Their characterization completes identification of the respective trans and cis isomers for the series of c-pendant macrocycles also including 1,4,8,11-tetraazacyclotetradecane-6-amine-13-carboxylate ((3), (4)) and 1,4,8,11-tetraazacyclotetradecane-6,13-diamine ((5), (6)). The complexes show limited distortion from octahedral geometry with the strain in the presence of the coordinated c-pendant carboxylate significantly reduced compared with that for the c-pendant amine in analogues, a consequence mainly of six-membered as opposed to five-membered chelate rings involving the pendant donor. A comparison of the physical properties for the trans isomers of the octahedral complexes of (1), (3), and (5), which reflect progressively increasing strain, is presented.

Reactions of But-2-yne and Hexafluorobut-2-yne with Dicarbonyl(η-pentamethylcyclopentadienyl)-cobalt, -rhodium and -iridium. Structure of the iridium complex (η-C5Me5)Ir2(CO)2(CF3C2CF3)3H

1978 ◽  
Vol 31 (9) ◽  
pp. 1937 ◽  
Author(s):  
PA Corrigan ◽  
RS Dickson ◽  
GD Fallon ◽  
LJ Michel ◽  
C Mok
Keyword(s):  
Major Product ◽  
Octahedral Geometry ◽  
Distorted Octahedral Geometry ◽  
Iridium Complex ◽  
Orthorhombic Space Group ◽  
Reaction Conditions ◽  
R Factor ◽  
Distorted Octahedral ◽  
A Cell ◽  
Dirhodium Complexes

The reactions of but-2-yne and hexafluorobut-2-yne with the complexes (η-C5Me5)M(CO)2, M = CO, Rh, or Ir, have been compared. A cyclopentadienone complex, (η-C5Me5)M[C4Me4CO]2 is the major product formed in the reaction of but-2-yne with (η-C5Me5)M(CO)2, M = Co or Rh. The cobalt system also gives some hexamethylbenzene whereas the rhodium system yields the pentadienone-dirhodium complex (q-C5Me5)2Rh2(MeC2Me)2CO. The cyclopentadienone complexes (η-C5Me5)M[C4(CF3)4CO], M = CO and Rh, were major products from the reactions of hexa- fluorobut-2-yne with (η-C5Me5)M(CO)2. Hexakis(trifluoromethyl)benzene and the tetrahapto- benzene complexes (η-C5Me5)M[η4-C6(CF3)6], M = Co or Rh, were minor products from these reactions. Small amounts of the dirhodium complexes (η-C5Me5)2Rh2(CF3C2CF3)2(CO)n, n = 1 or 2, were also isolated from the rhodium system under some reaction conditions. No products could be isolated from the reaction between (η-C5Me5)Ir(CO)2 and but-2-yne, but the reaction with hexafluorobut-2-yne gives two organoiridium complexes. One complex, (η-C5Me5)Ir(CO)2(CF3C2CF3), incorporates an iridiocyclobutenone ring and one terminal carbonyl. The second, (η-Ir5Me5)Ir2(CO)2(CF3C2CF3)3H, has been characterized crystallographically. The compound crystallizes with four molecules in the orthorhombic space group Pnma in a cell of di- mensions a 14.262(5), b 13.293(5), c 15.027(5) Ǻ. The structure has been refined by standard methods to a conventional R factor of 0.072, based on 2061 reflections above background. The environments of the two iridium atoms are markedly different. One forms part of a metallopentadiene ring, and it is also attached to two terminal carbonyls, a σ-bonded C(CF3)=C(CF3)H group, and the other iridium atom [Ir-Ir distance 2.737(1) Ǻ]. Overall, this iridium has a distorted octahedral geometry. The second iridium is n-bonded in a conventional sandwich manner to the C5Me5 and iridiocycle rings; these two rings have a staggered conformation and are close to parallel.

Crystal and Molecular Structure of the s-fac-[Co((S)-Asp)(medien)]ClO4 . H2O . HClO4 Isomer

1993 ◽  
Vol 58 (2) ◽  
pp. 335-342 ◽  
Author(s):  
Jan Ondráček ◽  
Jaroslav Maixner ◽  
Jana Ondráčková ◽  
František Jursík
Keyword(s):  
Molecular Structure ◽  
Crystal And Molecular Structure ◽  
Chelate Ring ◽  
Complex Cation ◽  
Heavy Atom ◽  
Boat Conformation ◽  
Membered Chelate Ring ◽  
Anisotropic Temperature ◽  
Hydroxonium Cation ◽  
Heavy Atom Method

The crystal and molecular structure of s-fac-[Co((S)-Asp)(medien)]ClO4 . H2O . HClO4 was elucidated by the heavy atom method. The positional parameters of the nonhydrogen atoms and their anisotropic temperature parameters were refined based on 2 474 observed reflection with final values of R = 0.0603 and wR = 0.0616. The substance crystallized in the orthorhombic system in the space group P212121, Z = 4, a = 8.536(1), b = 13.378(1), c = 16.899(2) Å. The structure comprises layers of the complex cation which alternate with layers containing two perchlorate anions and one hydroxonium cation. The five-membered chelate ring of 4-methyl-1,4,7-triazaheptane exist in the asymmetric λ, δ envelope conformations and the N-CH3 group of the triamine has the exo orientation. The five-membered ring of (S)-aspartic acid assumes the symmetric envelope conformation, the six-membered chelate ring, the skew boat conformation.

Structural Studies of Complexes of Tridentate Terimine Systems. Crystal Structure of Bis(2,2′:6′,2′′-terpyridine)ruthenium(II) Perchlorate Hydrate, Bis(2,2′:6′,2′′-terpyridine)- osmium(II) Perchlorate Hemihydrate and Bis((1,10-phenanthrolin-2-yl)(pyridin-2-yl)amine)iron(II) Tetrafluoroborate Dihydrate

1998 ◽  
Vol 51 (12) ◽  
pp. 1131 ◽  
Author(s):  
Donald C. Craig ◽  
Marcia L. Scudder ◽  
Wendy-Anne McHale ◽  
Harold A. Goodwin
Keyword(s):  
Crystal Structure ◽  
Crystal Structures ◽  
Metal Ion ◽  
Chelate Ring ◽  
Monoclinic Space Group ◽  
Structural Studies ◽  
Triclinic Space Group ◽  
Space Group ◽  
Membered Chelate Ring ◽  
Group I

The crystal structures of bis(2,2′:6′,2″-terpyridine)ruthenium(II) perchlorate hydrate, bis(2,2′:6′,2″- terpyridine)osmium(II) perchlorate hemihydrate and bis((1,10-phenanthrolin-2-yl)(pyridin-2-yl)- amine)iron(II) tetrafluoroborate dihydrate are described. In the terpyridine complexes the ruthenium-nitrogen distances and the corresponding osmium-nitrogen distances are not significantly different. In both complexes the ligand geometry and the metal ion environment show the distortions usual for bis(terpyridine) systems. Distortions are less marked in the bis((1,10-phenanthrolin-2-yl)(pyridin-2-yl)amine)iron(II) cation in which each tridentate unit forms one five-membered and one six-membered chelate ring. [Ru(trpy)2] [ClO4]2.(H2O)1.1: tetragonal, space group I 41/a, a, b 12·527(2), c 40·202(11) Å, Z 8. [Os(trpy)2] [ClO4]2.(H2O)0·5: monoclinic, space group P 21/n, a 8·842(3), b 8·861(1), c 39·22(2) Å, β93·89(2)°, Z 4. [Fe(phpyam)2] [BF4]2.(H2O)2: triclinic, space group P -1, a 12·43(1), b 12·45(1), c 13·35(1) Å, α 62·70(10), β 78·55(8), γ 72·46(9)°, Z 2.

Synthese und Kristallstruktur von (Cyclopentadienyl)(dicarbonyl)(1,5-di-/Molyl-pentaazadienido)molybdän, (Cp)Mo(CO)2(tolN5tol)/ Synthesis and Crystal Structure of (Cyclopentadienyl)(dicarbonyl)(1,5-di-p-tolyl-pentaazadienido)molybdenum, (Cp)Mo(CO)2(tolN5tol)

1988 ◽  
Vol 43 (8) ◽  
pp. 1029-1032 ◽  
Author(s):  
Johannes Beck
Keyword(s):  
Crystal Structure ◽  
Nitrogen Atom ◽  
Metal Atom ◽  
Chelate Ring ◽  
Lattice Parameters ◽  
Monoclinic Space Group ◽  
Synthesis And Crystal Structure ◽  
Space Group ◽  
Membered Chelate Ring

Abstract(Cp)Mo(CO)2(tolN5tol) is formed in the reaction of (Cp)Mo(CO)3Cl with tolNN(NH)NNtol and NaOH in ethanol. It forms red platelike crystals from THF/hexane which crystallize in the monoclinic space group P21/n with the lattice parameters a = 765.6(2), b = 2372.3(3), c = 1149.4(2) pm, β = 97.06(2)°, Z = 4. The structure consists of monomeric complexes. The pentaazadienido ligand chelates with its nitrogen atoms N1 and N3 the Mo atom of a (Cp)Mo(CO)2 unit. The nitrogen atom N5 is not coordinated to the metal atom. Although asymmetrically bonded, the all trans N5 zig zag chain is planar. The N -N distances in the four membered chelate ring are nearly equal (N1 - N2 = 131.0 and N2 - N3 = 132.6 pm)

Crystal Structure of Dibromo(η4-1,5-cyclooctadiene)palladium(II)

1996 ◽  
Vol 61 (9) ◽  
pp. 1335-1341 ◽  
Author(s):  
Petr Štěpnička ◽  
Ivana Císařová
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonds ◽  
Single Crystal ◽  
Boat Conformation ◽  
X Ray Diffraction ◽  
Orthorhombic Space Group ◽  
Space Group ◽  
X Ray ◽  
Square Planar ◽  
Twisted Boat

The crystal structure of [(η4-C8H12)PdBr2] has been determined by a single crystal X-ray diffraction with R = 3.82% for 2 147 independent diffractions. The compound crystallizes with the symmetry of orthorhombic space group P212121 (No. 19) within the following parameters: a = 7.0785(5) Å, b = 11.1896(9) Å, c = 12.514(1) Å, V = 991.2(1) Å3, Z = 4. The square planar arrangement of ligands around Pd(II) is distorted due to the steric requirements of 1,5-cyclooctadiene in a twisted boat conformation. Formula units are joined by the weak C2-H2...Br1(1 + x, y, z) hydrogen bonds.

An orthorhombic polymorph of a cyclization product of perindopril

2013 ◽  
Vol 69 (6) ◽  
pp. 630-633 ◽  
Author(s):  
Joanna Bojarska ◽  
Waldemar Maniukiewicz ◽  
Lesław Sieroń ◽  
Milan Remko
Keyword(s):  
Crystal Packing ◽  
Chair Conformation ◽  
Boat Conformation ◽  
Cyclization Product ◽  
Asymmetric Unit ◽  
Orthorhombic Space Group ◽  
Chain Molecules ◽  
Space Group ◽  
Significant Difference ◽  
Tetragonal Form

Low-temperature X-ray diffraction experiments were employed to investigate the crystal structures of an orthorhombic polymorph of the intramolecular cyclization product of perindopril, a popular angiotensive-converting enzyme (ACE) inhibitor, namely ethyl (2S)-2-[(3S,5aS,9aS,10aS)-3-methyl-1,4-dioxo-5a,6,7,8,9,9a,10,10a-octahydro-3H-pyrazino[1,2-a]indol-2-yl]pentanoate, C19H30N2O4, (Io), and its tetragonal equivalent, (It), which was previously reported at ambient temperature [Bojarskaet al.(2013).J. Chil. Chem. Soc.58, 1415–1417]. Polymorph (Io) crystallizes in the orthorhombic space groupP212121with two molecules in the asymmetric unit, while tetragonal form (It) crystallizes in the space groupP41212 with one molecule in the asymmetric unit. The geometric parameters of (Io) are very similar to those of (It). The six-membered rings in both polymorphs adopt a slightly deformed chair conformation and the piperazinedione rings are in a boat conformation. However, the proline rings adopt an envelope conformation in (Io), while in (It) the ring exists in a slightly deformed half-chair conformation. The most significant difference between the two structures is the orientation of the ethyl pentanoate chain. Molecules associate in pairs in a head-to-tail manner forming infinite columns. In (Io), molecules are related by a twofold screw axis forming identical columns, while in (It), molecules in successive neighbouring columns are related by alternating twofold screw axes and fourfold screw axes. In both cases, the crystal packing is stabilized by weak intermolecular C—H...O interactions only.

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