The syntheses and crystal structures of two chromium(III) and molybdenum(III) coordination compounds with 4-ethylpyridine

The structures of trichlorotris(4-ethylpyridine)chromium(III), [CrCl₃(C₇H₉N)₃] (I), and trichlorotris(4-ethylpyridine)molybdenum(III), [MoCl₃(C₇H₉N)₃] (II), consist of neutral molecules where three 4-ethylpyridine and three chloro ligands coordinate to the metal with a meridional configuration. Compound I crystallizes in a trigonal space group P3₁ with a = 11.515(2) Å and c = 15.378(3) Å. Compound II crystallizes in a monoclinic space group C2/c with a = 24.200(3) Å, b = 18.089(3) Å, c = 22.6004(7) Å and = 106.7137(6)°.     

Chemistry of diaminomaleonitrile: synthesis and structure of two unexpected products from its condensation with 2,5-hexanedione

For the synthesis of precursors to cellulose-based ion exchange materials, the condensation of diaminomaleonitrile with 2,4-pentanedione and 2,5-hexanedione was explored. Whilst the former diketone yielded the expected 1,4-diazepine (2), the latter gave either a pyrrole derivative (3) or an unusual triazabicyclononene (4), depending on the conditions used. Compound 2 crystallizes in the monoclinic space group P2₁/c with a = 8.9313(10) Å, b = 9.0370(7) Å, c = 11.4448(9) Å, = 102.48(8)°, V = 901.89(14) ų, and Z = 4. Compound 3 crystallizes in the orthorhombic space group Pna2₁ with a = 12.0342(8) Å, b = 8.3760(8) Å, c = 10.7026(11) Å, V = 1078.81(17) ų, and Z = 4. Compound 4 crystallizes in the monoclinic space group P2₁/c with a = 9.0157(5) Å, b = 13.5374(9) Å, c = 12.8751(16) Å, = 99.506(5)°, V = 1549.82(15) ų, and Z = 4. In both 3 and 4 the aminovinyl substituent shows evidence for involvement of the lone pair on nitrogen with the carbon -system. Also, 3 and 4 are highly associated in the solid state via hydrogen bonding.     

Crystal and molecular structure of bis(imazapyr)diaqua copper(II)

The imidazolinone herbicide imazapyr, 2-(4-isopropyl-4-methyl-5-oxo-2-imidazolin-2-yl)nicotinic acid (H₂imz) interacts with Cu(II) leading to [Cu(Himz)₂(H₂O)₂] which crystallizes in the space group Pbca, with a = 12.5370(3) Å, b = 19.8500(5) Å, c = 22.7720(9) Å, and Z = 8. The Cu(II) atom is octahedrally surrounded by four nitrogen atoms of two Himz^– anions and two water molecules. Each Himz^– acts as a chelating ligand by means of N pyridine and N lactam atoms leading to five-membered chelate rings. The Cu N distances vary from 1.948(4) to 2.299(5) Å while the Cu O are 2.114(5) and 2.256(6) Å. The imidazol N-H are involved in short intramolecular hydrogen bonds with the carboxylate groups. The structure is stabilized by an intermolecular hydrogen-bonded network involving the water molecules and the carboxylate groups.     

Synthesis and crystal structures of four nickel(II) 1,5-naphthalenedisulfonate compounds

Four nickle(II) 1,5-naphthalenedisulfonate (1,5nds) complexes, namely [Ni(H₂O)₆] (1,5nds) (1), trans-[Ni(en)₂(H₂O)₂](1,5nds)·2H₂O (2), [Ni(tren)(H₂O)₂](1,5nds)·H₂O (3), and [Ni(dien)₂](1,5nds)·2H₂O (4), where en = ethylenediamine, tren = tris(2-aminoethyl)amine, and dien = diethylenetriamine, have been synthesized and structurally characterized. Compound 1 crystallizes in space group P2₁/c, with a = 13.200(2) Å, b = 6.6197(10) Å, c = 9.6001(14) Å, and = 92.005(3)° compound 2 crystallizes in space group C2/c, with a = 15.698(2) Å, b = 13.006(2) Å, c = 12.845(2) Å, and = 119.262(4) Å compound 3 crystallizes in space group P , with a = 8.8971(10) Å, b = 11.5440(13) Å, c = 11.9169(14) Å, = 77.254(2)°, = 74.079(2)°, and = 82.162(2)° compound 4 crystallizes in space group P2₁/c, with a = 10.3600(13) Å, b = 12.5650(16) Å, c = 9.9853(12) Å, and = 103.599(2)°. Compound 1 crystallizes in a typical inorganic–organic layered structure adopted by metal naphthalenesulfonate, while compounds 2–4 crystallize in a hybrid inorganic–organic pattern. Unlike their Cu²⁺ analogue, the sulfonate does not coordinate directly to Ni²⁺. The hydrogen bonds formed between sulfonate and water molecules are the predominant packing forces for all structures. The inherited inversion center of the 1,5nds anion is carried into the crystal structure and results in centrosymmetric crystallization of all compounds.     

Crystal structures of diphosphinated group 6 Fischer alkoxy carbenes

The crystal structures of four diphosphinated Group 6 Fischer alkoxy carbenes with the compositions fac-(dppe)(CO)₃M–C(OR)(R) (R = Me, R = Et, M = Cr, 1; R = Ph, R = Me, M = Cr, 2; R = Me, R = Me, M = W, 3; R/OR = 3-methyl-2-oxacyclopentylidenyl, M = Cr, 4) have been determined at 243 K. Compound 1 crystallizes in the monoclinic system, space group P2₁/c with a = 11.2243(11) Å, b = 18.5998(18) Å, c = 15.1260(15) Å, = 107.056(4), V = 3019.0(5) ų, and Z = 4. Compound 2 crystallizes in the monoclinic system, space group P2₁/c with a = 11.8102(9) Å, b = 18.3152(14) Å, c = 15.0262(12) Å, = 93.753(3), V = 3243.3(4) ų, and Z = 4. Compound 3 crystallizes in the monoclinic system, space group P2₁/c with a = 11.3458(6) Å, b = 18.5772(9) Å, c = 15.3883(8) Å, = 108.576(6), V = 3074.5(3) ų, and Z = 4. Compound 4 crystallizes in the orthorhombic system, space group Pna2₁ with a = 22.6509(14) Å, b = 9.8118(6) Å, c = 13.7507(8) Å, V = 3056.0(3) ų, and Z = 4. Steric repulsions with the dppe ligand favor a conformation with the alkoxy moiety directed toward the dppe backbone, in an E geometry, in 1–4.     

Crystal and molecular structure of Rebek's imide

The crystal and molecular structure of Rebek's imide 1 is reported. Crystal data for 1: triclinic, space group , a = 7.8733(7) Å, b = 12.712(1) Å, c = 12.789(1) Å, = 86.628(5)°, = 84.628(5)°, = 72.981(5)°, V = 1217.9(2) ų, and D _c = 1.305 g/cm³ for Z = 2 and R = 0.047. The molecule crystallizes as a cyclic, hydrogen-bonded dimer held together by two N H...O and two O H...O hydrogen bonds involving amide...carboxylic acid interactions. The dimer organizes in the solid state to form 1D ribbons.     

Crystal structures of 4,7-phenanthrolino-5,6:5′,6′-pyrazine tetrahydrate and 1,4,5,8,9,12-hexaazatriphenylene dihydrate

The crystal structures of 4,7-phenanthrolino-5,6:5,6-pyrazine tetrahydrate (I) and 1,4,5,8,9,12-hexaazatriphenylene dihydrate (II) have been determined from low temperature (173 K) x-ray single crystal diffraction data. I crystallizes in the triclinic system, space group P with a = 11.2687(6), b = 12.4766(6), c = 12.7068(7) Å, = 113.4740(10), = 91.605(2), = 114.587(2)°, V = 1449.33(13) ų, and Z = 4. II crystallizes in the orthorhombic system, space group Pca2₁ with a = 18.187(2), b = 9.2576(11), c = 6.9672(8) Å, V = 1173.0(2) ų, and Z = 4. In both structures the planar heterocyclic molecules stack with interplanar distances down to 3.3 Å, which is consistent with self--complexation. The crystal water molecules provide links between the columns of stacked molecules through hydrogen bonds. In each compound the N-C bond lengths fall into two distinct groups (mean values 1.330(3) vs 1.361(1) Å in I and 1.320(3) vs 1.357(5) Å in II), as do the C-C bonds of the central phenyl rings (1.411(4) vs 1.467(1) Å in I and 1.405(5) vs 1.458(4) Å in II).     

Crystal structure of 751-1751-1751-1751-2751-2751-2

The title compound crystallizes in the centrosymmetric triclinic space group (No. 2) witha=10.818(1)Å,b=10.876(1)Å,c=11.072(2)Å, =98.74(1)°, =98.83(1)°, =96.61(1)°,V=125906(3)ų andZ=2. Interatomic distances include Fe–P=2.243(2)Å, Fe–CO=1.771(6)–1.781(5)Å, Fe–C(C₅H₅)=2.074(6)–2.103(5)Å and P–F=1.511(6)–1.571(4)Å.     

Crystal structure and thermal analysis of 1,5-diammonium-2-methyl pentane sulfate monohydrate

Chemical preparation, x-ray single crystal, and thermal analysis of C₆H₁₈N₂SO₄·H₂O (denoted DMPS) are described. The compound crystallizes in the triclinic system with P space group. Its unit cell dimensions are a = 5.826(1) Å, b = 10.014(1) Å, c = 11.221(1) Å, = 66.716(1)°, = 84.395(1)°, = 83.759(1)°, V = 596.7(1) ų, and Z = 2. The DMPS structure is built up from inorganic chains parallel to the a axis and linked via O(W)-H···O hydrogen bonds. These chains are interconnected by organic groups. Thermal analysis reveals the presence of one water molecule in the structure and shows a reversible weak phase transition.     

Crystal structure of (diphenyl)(morpholino)phosphiniminocyclotrithiazene

The title compound (C₆H₅)₂(OC₄H₈N)P=N–S₃N₃ crystallizes in the space group with unit cell parametersa=9.3900(2),b=9.4747(1),c=11.3850(3) Å, =95.73(4), =96.85(6), =104.26(2)^o, and Z=2. The tricoordinated sulfur of the cyclotrithiazene ring deviates from the mean plane of other skeletal atoms by 0.683(4) Å. The angle at this atom is the smallest in the ring and is enclosed by the longest S–N bonds observed in the ring.     

2-Amino-1,2,3-triazole derivatives

The syntheses and structure of 2-triarylphosphoranimine-1,2,3-triazole derivatives from vicinal diazides have been investigated. Compounds derived from dichloronapththoquinone, 2,3-dichloro-5,6-dimethylbenzoquinone, and 2,3,5,6-tetrachlorobenzoquinone are included. X-ray structures, NMR, IR, UV, and cyclic voltammetry data are reported. Compound 2 crystallizes in space group with a = 12.31(1), b = 12.469(3), c = 10.088(3) Å, = 97.19(3), = 103.79(6), = 101.84(4)°, and D _calc = 1.466 g/cm for Z = 2. Compound 4 crystallizes in space group P2₁/c with a = 9.044(2), b = 10.882(2), c = 19.110(4) Å, = 99.06(2)°, and D _calc = 1.324 g/cm for Z = 2. Compound 6 crystallizes in space group P2₁/a with a = 8.85(1), b = 14.841(8), c = 11.372(8) Å, = 107.19(3)°, and D _calc = 1.397 g/cm for Z = 4. Compound 11 crystallizes in space group P2₁/n with a = 8.823(3), b = 16.501(6), c = 16.221(3) Å, = 103.58(2)°, and D _calc = 1.309 g/cm for Z = 4. Compound 12 crystallizes in space group with a = 11.606(8), b = 11.671(5), c = 10.734(3) Å, = 101.62(3), = 93.70(4), = 64.33(4)°, and D _calc = 1.438 g/cm for Z = 2. Compound 13 crystallizes in space group C2/c with a = 13.337(7), b = 9.217(6), c = 24.78(1) Å, = 102.85(5)°, and D _calc = 1.478 g/cm for Z = 8.     

Synthesis and crystal structure of [Cu(azpy)(H2O)4][Cu2(nta)2(azpy)]····6H2O: A two-dimensional network solid

The copper(II) complex [Cu(azpy)(H₂O)₄][Cu₂(nta)₂(azpy)]····6H₂O (nta = nitrilotriacetate, azpy = 4,4-azobispyridine) has been synthesized and structurally characterized. It crystallizes in the triclinic space group P , a = 8.6985(3) Å, b = 9.4776(3) Å, c = 14.6544(5) Å, = 71.5360(10)°, = 85.7600(10)°, = 88.1420(10)°, V = 1142.74(7) ų, Z = 1. The crystal structure consists of one-dimensional linear chain cations and dimeric anions. The copper centers in the anion possess distorted trigonal bipyramidal geometry, while Cu(2) has a distorted octahedral geometry in the cation. Coordinated water molecules in the one-dimensional chain form interionic hydrogen bonds with the oxygen atoms of the carboxylate of nta of the dimmer anion. These hydrogen bonds result in the formation of a two-dimensional network.     

Solid state structure of 4,4,6,6-tetraphenylcyclohex-2-en-1-one

Synchrotron data allowed the crystal structure determination of 4,4,6,6-tetraphenylcyclohex-2-en-1-one (1). The cyclohexenone ring is in a half-chair conformation ³H₂violating the planarity of a conjugated -system. The geometry of 1 optimized with semiempirical and density functional theory calculations is in good agreement with the experimental data. Compound 1 crystallizes in triclinic space group with unit cell parameters a = 9.7995(19) Å, b = 10.5263(32) Å, c = 12.2001(37) Å, = 96.916(10)°, = 112.971(10)°, = 102.589(10)°, V = 1100.86(17) ų, and Z = 2.     

Synthesis,X-ray structure determination and analysis of packing interactions in 9-(1,2-propenyl)-6-carboethoxy-2-methyl-2,3-dihydrofuro[2,3-h]-benzopyran-5H-one

Claisen rearrangement of ethyl-2,4-diallyloxy--carbethoxycinnamate (1) in refluxing DMA afforded ethyl-9-allyl-2-methyl-2,3-dihydrofuro(2,3-h)benzopyran-5H-one-6-carboxylate (2) in a single step. Dehydrogenation with Pd/C (10%) in DPE furnished an unexpected isomeric compound, 9-(1,2-propenyl)-6-carbethoxy-2-methyl-2,3-dihydrofuro[2,3-h]-benzopyran-5H-one (3). This compound, C₁₈H₁₈O₅, crystallizes in the monoclinic space group P2₁/n with unit cell parameters, a = 7.346(1), b = 16.482(3), c = 12.653(2),Å, and = 92.71(1)°. The structure has been solved by direct methods and refined to R = 0.056 for 1719 observed reflections. The coumarin nucleus is planar. The five-membered ring is in envelope-conformation. The crystal structure is stabilized by intra- and intermolecular CHO hydrogen bonds.     

Polyhedral palladaborane chemistry: isolation and structural characterization of ten-vertex [(PMe2Ph)2PdB9H12(PMe2Ph)] and eleven-vertex [(PMe2Ph)2PdB10H12]

Ten-vertex [6,6-(PMe₂Ph)₂-arachno-6-PdB₉H₁₂-9-(PMe₂Ph)] 1a and eleven-vertex [7,7-(PMe₂Ph)₂-nido-7-PdB₁₀H₁₂] 2a have been isolated as occasional by-products from an extension to palladaborane chemistry of the one-pot route for the preparation of the nine-vertex platinaborane [(PMe₂Ph)₂PtB₈H₁₂] 3b from [PtCl₂(PMe₂Ph)₂] and B₁₀H₁₄, but using [PdCl₂(PMe₂Ph)₂] instead of [PtCl₂(PMe₂Ph)₂] to generate [4,4-(PMe₂Ph)₂-arachno-4-PdB₈H₁₂] 3a in yields of upto 75%. The two by-products 1a and 2a are each characterized by single-crystal X-ray diffraction analysis. Space group and cell parameters are as follows: for 1a, triclinic, , a = 10.1139(2) Å, b = 10.3955(2) Å, c = 31.5086(7) Å, = 94.4720(12)°, = 91.6420(10)°, and = 105.3790(11)°; for 2a, monoclinic, P2₁/n, a = 14.6059(3) Å, b = 10.9988(2) Å, c = 15.1516(3) Å, and = 93.0000(14)°. Whereas 1a and 1b are isomorphous, Compounds 2a and 2b are not, and show significant differences in intramolecular conformation.     

The crystal structures of two reaction products of α-halopyruvamide with nitrogen and sulfur nucleophiles

Two compounds have been prepared during the investigation of the reactivity of -halopyruvamides. The reaction products: 3-(4-chlorophenyl)imidazo[1,2-a]pyridine-2-carboxamide (1) and 7-carbamoyl-5-phenyl-2,3-dihydro[1,3]thiazolo[4,3-b][1,3]thiazol-4-ium chloride (2) were structurally characterized by x-ray crystallography. Compound 1 crystallizes in the orthorhombic space group Pca2₁ with a = 28.813(2), b = 9.369(1), and c = 9.361(1) Å. The structure contains two crystallographically different molecules. Compound 2 crystallizes in the monoclinic space group P2₁/c with the following cell parameters: a = 8.5895(8), b = 22.499(2), c = 7.4133(6) Å, and = 110.204(1)°.     

Crystal and molecular structure of [(C6H5)2P(=0)(CH2CH2N(CH3)3 +][I−]

The title compound crystallizes in the centrosymmetric triclinic space group withZ=4. The crystallographic asymmetric unit contains two independent cations; interatomic distances within these include P=O=1.47(1) and 1.47(1) Å, P–C₆H₅=1.78(2)–1.81(1)Å and P–CH₂CH₂NMe₃ ⁺=1.80(1) and 1.81(1) Å. The phosphine oxide moiety is involved in intermolecular hydrogen bonding ()...H–C, with O...H2.42Å) and the iodide is involved in I...H–C contacts with I...H3.10Å.     

Complexes of silicon tetrabromide with pyridine and 3,5-dimethylpyridine

The crystal structures of trans-tetrabromobis(pyridine)silicon (1) and trans-tetrabromobis(3,5-dimethylpyridine)silicon (2) have been determined: (1) crystallizes in the monoclinic space group C2/m with cell dimensions a = 14.4250(2) Å, b = 7.3055(1) Å, c = 7.2839(1) Å, = 117.660(1)°, (2) crystallizes in the monoclinic space group C2/m with cell dimensions a = 16.013(3) Å, b = 7.316(1) Å, c = 8.179(2) Å, = 113.19(1)°. Both molecules, with D_2h symmetry, have crystallographic C_2h site symmetry. The environment about the Si atoms can be described as a slightly distorted octahedron with the pyridyl ligands occupying axial positions and the four bromo ligands in the equatorial plane.     

Tris(triphenylphosphine)rhodium cyano and triphenylcyanoborate complexes: Structures and a DFT study

The structures of [Rh(CN)(PPh₃)₃](EtOH) (1), [Rh(NCBPh₃)(PPh₃)₃] (2), and [Rh(CNBPh₃)(PPh₃)₃] (3) are reported together with a density functional theory (DFT) study of the model compounds [Rh(NCBH₃)(PH₃)₃] and [Rh(CNBH₃)(PH₃)₃]. Compound 1 crystallizes in space group Pc with a = 10.4798(15) Å, b = 12.5410(18) Å, c = 19.974(3) Å and = 112.215(6)°; compound 2 crystallizes in space group with a = 12.929(2) Å, b = 14.362(2) Å, c = 17.575(3) Å and = 92.544(3)°, = 90.214(3)°, = 113.831(3)°; compound 3 crystallizes in space group with a = 12.915(2), b = 14.296(2), c = 17.664(3) Å and = 92.469(3)°, = 90.088(3)°, = 113.768(3)°. All three complexes show slight tetrahedral distortion from ideal square planar geometry (largest for 1). Differences in the reactivity and stability of 2 and 3 are interpreted according to the results of a density functional theory study.     

Structure and properties of cobalt(II) complex with a tetraaza macrocycle containing 2-pyridylmethyl pendant arms

The complex [Co(L)]Cl₂·10H²O (1) (L = 2,13,-bis(2-pyridylmethyl)-3,14-dimethyl-2,6,13,17-tetraazatricyclo[14,4,0^1.18,0^7.12]docosane) has been synthesized and structurally characterized. Compound 1 crystallizes in the triclinic system, space group P-1 with a = 9.731(2) Å, b = 9.789(2) Å, c = 11.998(1) Å, = 66.66(1)°, = 76.95(1)°, = 87.99(2)°, V = 1020.4(3) ų, and Z = 1. The crystal structure of 1 shows that the complex is centrosymmetric and the cobalt(II) ion has a slightly distorted octahedral geometry with four nitrogen atoms of the macrocycle and two nitrogen atoms of the pendent arms at the axial positions. Cyclic voltammetry for 1 undergoes reversible one-electron oxidation to the Co(III) and irreversible one-electron reduction to the Co(I).