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

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.

1997 ◽  
Vol 50 (9) ◽  
pp. 903 ◽  
Author(s):  
Trevor W. Hambley ◽  
Walter C. Taylor ◽  
Stephen Toth

Four novel norditerpenoids were isolated from a new encrusting sponge, conveniently labelled Aplysilla pallida. The structures of aplypallidenone (1), aplypallidoxone (2), aplypallidione (3) and aplypallidioxone (4) were elucidated by spectroscopic studies and the crystal structures of aplypallidenone and aplypallidoxone have been determined by X-ray diffraction methods. The structure of (1) was refined to a residual of 0·040 for 1665 independent observed reflections and the structure of (2) was refined to a residual of 0·031 for 1699 independent observed reflections. The crystals of (1) are orthorhombic, space group P212121, a 7·728(2), b 10·838(4), c 24·880(5) Å, Z 4. Those of (2) are monoclinic, space group C 2, a 23·927(7), b 6·674(2), c 14·033(3) Å, Z 4.


1998 ◽  
Vol 51 (12) ◽  
pp. 1131 ◽  
Author(s):  
Donald C. Craig ◽  
Marcia L. Scudder ◽  
Wendy-Anne McHale ◽  
Harold A. Goodwin

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.


1983 ◽  
Vol 61 (3) ◽  
pp. 427-433 ◽  
Author(s):  
Miroslaw Cygler ◽  
Janusz Skolimowski

Crystal structures of 2,2,6,6-tetramethyl-4,4-diphenyl-1,4-azaphosphorinanium perchlorate (I) and 2,2,6,6-tetramethyl-4-oxo-4-phenyl-1,4-azaphosphorinan-1-oxyl (II) were determined. Compound I crystallizes in the monoclinic space group C2/c with unit cell dimensions a = 18.2967(7), b = 10.9413(6), c = 20.8714(13) Å, β = 90.79(1)° (at 115 K), and II crystallizes in the orthorhombic space group Pn21a with a = 8.076(1), b = 10.139(1), c = 17.894(1) Å. Intensity data were measured on a diffractometer at 115 K for I and at the room temperature for II. The structures were solved by a combination of heavy-atom and direct methods and refined to R = 0.036 (3968 reflections) for I and 0.039 (1451 reflections) for II.The azaphosphorinane ring adopts a chair conformation in both molecules, being flattened in the P part in I and in the N part in II. In molecule I the equatorial phenyl group is nearly parallel to the approximate plane of symmetry of the molecule, and the axial phenyl group is perpendicular to that plane. In molecule II the P=O bond is axial and the phenyl group is equatorial. The CN(O)C group is not planar. The N—O bond makes an angle of 18.0(3)° with the CNC plane. The CNC angle of 129.3(3)° is larger than that found in nitroxypiperidine analogues.


1987 ◽  
Vol 40 (5) ◽  
pp. 829 ◽  
Author(s):  
NF Curtis ◽  
GJ Gainsford ◽  
P Osvath ◽  
DC Weatherburn

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.


2020 ◽  
Vol 75 (5) ◽  
pp. 509-516 ◽  
Author(s):  
Timotheus Hohl ◽  
Torben Sinn ◽  
Constantin Hoch

AbstractFour solvent complexes of beryllium iodide were prepared by dissolving BeI2 in N,N-dimethyl formamide (DMF), pyridine (Pyr), N-methyl pyrrolidone (NMP) and 2,6-dimethyl pyridine (2,6-lutidine, Lut). Their crystal structures were established from single crystal X-ray diffraction. For [Be(DMF)4]I2 a new modification is reported (monoclinic, space group P21/c, a = 12.491(2), b = 11.593(2), c = 15.310(3) Å, β = 94.7073(6)°). In [Be(Pyr)4]I2 (monoclinic, space group C2/c, a = 17.8799(13), b = 7.6174(5), c = 18.2611(14) Å, β = 113.508(4)°) and [Be(NMP)4]I2 (orthorhombic, space group Pbca, a = 13.941(5), b = 15.754(3), c = 24.634(7) Å) homoleptic tetrahedral complex cations are formed, while the sterically demanding solvent ligand Lut yields a neutral complex with covalently bound iodine ligands [BeI2(Lut)2] (monoclinic, space group P21/c, a = 7.8492(9), b = 24.265(3), c = 27.037(3) Å, β = 97.076(3)°). Their electrochemical stability with respect to their application as beryllium electrolytes for deposition of beryllium from solution is discussed.


1986 ◽  
Vol 39 (11) ◽  
pp. 1823 ◽  
Author(s):  
CHL Kennard ◽  
EJ Oreilly ◽  
S Schiller ◽  
G Smith ◽  
AH White

The crystal structures of 2-fluorophenoxyacetic acid ( oflpaH ) and the metal complexes aquabis (2-fluorophenoxyacetato) bis (pyridine)copper(II) (1) and tetraaquabis (2-fluorophenoxyacetato)zinc(II) dihydrate (2) have been determined by X-ray diffraction and refined to residuals R 0.036, 0.041, 0.025 for 641, 863 and 1505 observed reflections respectively. The acid crystallizes in a monoclinic cell, space group P21/c with a 6.207(2), b 19.363(8), c 6.999(2) Ǻ, β 114.81(2)� and Z 4. The molecules form planar, centrosymmetric , hydrogen-bonded cyclic dimers [O...O, 2.618(4)Ǻ]. Complex (1) is orthorhombic, space group P2cb with two molecules in a cell of dimensions a 5.621 (2), b 17.218(7), c 13.288(6)Ǻ while (2) is monoclinic, space group P21/c, a 6.597(2), b 5.279(2), c 30.079(10) Ǻ, β 94.65(3)�; with Z 2. Complex (1) has square-pyramidal geometry with the basal plane containing two trans related carboxyl oxygens [Cu-O, 1.944(4)Ǻ] and two trans related pyridine nitrogens [Cu-N, 2.030(5)Ǻ]. A water molecule occupies the apex of the square pyramid [Cu-OW, 2.199(8)Ǻ]. Complex (2) has octahedral geometry with the MO6 octahedron containing two trans related carboxyl oxygens [Zn-O, 2.122(2)Ǻ] and four water oxygens [Zn-OW, 2.069(2), 2.085(2)Ǻ]. Preliminary X-ray data also confirm that the magnesium(II) and manganese(II) complexes of 2-fluorophenoxyacetic acid are isomorphous with (2) but different from the cobalt(II) derivative.


1985 ◽  
Vol 63 (6) ◽  
pp. 1166-1169 ◽  
Author(s):  
John F. Richardson ◽  
Ted S. Sorensen

The molecular structures of exo-7-methylbicyclo[3.3.1]nonan-3-one, 3, and the endo-7-methyl isomer, 4, have been determined using X-ray-diffraction techniques. Compound 3 crystallizes in the space group [Formula: see text] with a = 15.115(1), c = 7.677(2) Å, and Z = 8 while 4 crystallizes in the space group P21 with a = 6.446(1), b = 7.831(1), c = 8.414(2) Å, β = 94.42(2)°, and Z = 2. The structures were solved by direct methods and refined to final agreement factors of R = 0.041 and R = 0.034 for 3 and 4 respectively. Compound 3 exists in a chair–chair conformation and there is no significant flattening of the chair rings. However, in 4, the non-ketone ring is forced into a boat conformation. These results are significant in interpreting what conformations may be present in the related sp2-hybridized carbocations.


1992 ◽  
Vol 47 (3) ◽  
pp. 305-309 ◽  
Author(s):  
Anja Edelmann ◽  
Sally Brooker ◽  
Norbert Bertel ◽  
Mathias Noltemeyer ◽  
Herbert W. Roesky ◽  
...  

Abstract The Molecular Structures of [2,4,6-(CF3)3C6H2S]2 (1) [2,4,6-Me3C6H2Te]2 and [2-Me2N-4,6-(CF3)2C6H2Te]2 (3) have been determined by X-ray diffraction. Crystal data: 1: orthorhombic, space group P212121, Z = 4, a = 822.3(2), b = 1029.2(2), c = 2526.6(5) pm (2343 observed independent reflexions, R = 0.042); 2: orthorhombic, space group Iba 2, Z = 8, a = 1546.5(2), b = 1578.4(2), c = 1483.9(1) pm (2051 observed independent reflexions, R = 0.030); 3: monoclinic, space group P 21/c, Z = 4, a = 1118.7(1), b = 1536.5(2), c = 1492.6(2) pm, β = 98.97(1)° (3033 observed independent reflexions, R = 0.025).


1988 ◽  
Vol 41 (3) ◽  
pp. 283 ◽  
Author(s):  
GB Robertson ◽  
PA Tucker

The structures of two crystalline modifications of mer -(Pme2Ph)3H-cis-Cl2IrIII, (1), have been determined from single-crystal X-ray diffraction data. Modification (A) is monoclinic, space group P21/c with a 12.635(1), b 30.605(3), c 14.992(2)Ǻ, β 110.01(2)° and Z = 8. Modification (B) is orthorhombic, space group Pbca with a 27.646(3), b 11.366(1), c 17.252(2)Ǻ and Z = 8. The structures were solved by conventional heavy atom techniques and refined by full-matrix least- squares analyses to conventional R values of 0.037 [(A), 8845 independent reflections] and 0.028 [(B), 5291 independent reflections]. Important bond lengths [Ǻ] are Ir -P(trans to Cl ) 2.249(1) av. (A) and 2.234(1) (B), Ir -P(trans to PMe2Ph) 2.339(2) av. (A) and 2.344(1), 2.352(1) (B), Ir-Cl (trans to H) 2.492(2), 2.518(2) (A) and 2.503(1) (B) and Ir-Cl (trans to PMe2Ph)2.452(2) av. (A) and 2.449(1)(B). Differences in chemically equivalent metal- ligand bond lengths emphasize the importance of non-bonded contacts in determining those lengths.


1994 ◽  
Vol 49 (6) ◽  
pp. 770-772 ◽  
Author(s):  
Klaus Schulbert ◽  
Rainer Mattes

The reactions of N-substituted dithiocarbamic acid esters and nickel acetate yield, by partial degradation of the esters, the polynuclear nickel thiolato complexes cyclo-[(μ-SMe)2Ni]6, 1 and [(μ-SMe)2(Ni(MeNHCS2))2, 2. Their crystal structures have been determined. The Ni coordination spheres are comprised of four sulfur atoms in a planar arrangement. 1 is a second, highly symmetrical modification of the already known cyclic hexamer Ni6(SMe)12. In 2 two Ni(PhNHCS2) moieties are bridged to dimers by thiolato groups. Two of these dimers are connected to a tetramer by weak axial Ni-S interactions. Crystal data for 1: monoclinic, space group P21/n, a = 986.1(2), b = 1308.1(3), c = 1228.6(2) pm, β = 96.07(3)°, Z = 2, R = 0.072, Rw = 0.062, 3797 reflections. 2: orthorhombic, space group Pnma, a = 1790.0(4), b = 1806.7(4), c = 934.4(2) pm. Z = 4, R = 0.061, Rw = 0.051, 2079 reflections


Sign in / Sign up

Export Citation Format

Share Document