Synthesis,Structure, and Two Polymorphs of 4-((1,3-Dioxoisoindolin-2-yl)methyl)-1-methoxypyridinium tetrafluoroborate

Abstract  

4-((1,3-Dioxoisoindolin-2-yl)methyl)-1-methoxypyridinium tetrafluoroborate, C₁₅H₁₃BF₄N₂O₃, 1, was obtained by alkylation of the corresponding N-oxide and has been characterized by ¹H and ¹³C NMR, IR, UV spectroscopy and by X-ray crystallography. The crystal undergoes a reversible phase transition between 173 and 293 K. At room temperature, crystals are orthorhombic, space group Pna2₁ with a = 7.2487(3) ?, b = 17.8359 (8) ?, c = 12.4077(6) ?, V = 1604.16(12) ?³, and Z = 4. At 173 K, cations adopt four conformations in monoclinic space group Cc with a = 24.7076(29) ?, b = 14.4145(9) ?, c = 21.8765(25) ?, β = 126.249(17)°, V = 6283.3(7) ?³, and Z = 16. The compound is photostable in the crystal and does not undergo homolytic N–O bond cleavage as observed in solution.     

Microwave Synthesis and Crystal Structure of 2-Hydroxy-3-iodo-benzaldehyde-copper (II)

Abstract  

One new complex, 2-hydroxy-3-iodo-benzaldehyde-copper (II) has been designed and microwave synthesized. The structure was determined by UV, IR and single X-ray crystallography study. The title complex C₁₄H₈CuI₂O₄ crystallizes in the orthorhombic space group Pna2₁ with the cell parameters a = 12.7897(12) ?, b = 6.1132(8) ?, c = 19.5114(18) ?, V = 1525.5(3) ?³ and Z = 4. The central copper (II) is four-coordinated by four oxygen atoms from two 3-iodosalicylaldehyde. The complex is linked into rhombic crystals by weak intermolecular interactions.     

Crystal Structures of Two Palladacycles from the C–H Activation of 2-(Thiophen-2-yl)pyridine

Abstract  

A C,N-bound palladacycle dimer has been synthesised by reaction of 2-(thiophen-2-yl)pyridine, LH, with palladium acetate in acetic acid. Characterisation by single crystal X-ray diffraction showed the palladacycle dimer, [(L)Pd(OAc)]₂, to crystallise in the monoclinic space group P2₁/n with cell parameters a = 9.5853(1) ?, b = 19.1332(3) ?, c = 12.3889(2) ?, β = 103.732(1)°. Reaction of [(L)Pd(OAc)]₂ with triphenylphosphine afforded a trans-substituted monomeric complex, [(L)PdPPh₃(OAc)] which was also analysed using single crystal X-ray diffraction. [(L)PdPPh₃(OAc)] crystallises in the monoclinic space group P2₁/c with cell parameters a = 9.4839(1) ?, b = 11.0427(2) ?, c = 26.0770(4) ?, β = 95.022(1)°.     

Crystal Structures of N-(4-butyryl-3-hydroxyphenyl)acetamide Monohydrate and 4-(4-Chlorophenyl)-2-methyl-4-oxobutanoic Acid: Possibilities of Yang Photocyclization

Abstract  

N-(4-butyryl-3-hydroxyphenyl)acetamide monohydrate, (I), and 4-(4-chlorophenyl)-2-methyl-4-oxobutanoic acid, (II), are photochemically inert, which is a result of their conformation. The geometrical parameters describing the molecular conformation and possibilities of the Yang photocyclization in crystals have been calculated and discussed. Compound (I) forms double ribbons along the a axis, stabilized by hydrogen bonds and π⋯π interactions. Compound (II) forms dimers. (I): triclinic, space group \textP[`1] {\text{P}}\bar{1} , a = 6.9291(12) ?, b = 7.5736(16) ?, c = 13.0528(18) ?, α = 79.643(17)°, β = 85.818(15)°, γ = 63.97(2)°, Z = 2. (II): monoclinic, space group P2₁/c, a = 11.904(2) ?, b = 9.6508(12) ?, c = 10.666(2) ?, β = 110.64(2)°, Z = 4.     

Li<Subscript>2</Subscript>HPO<Subscript>3</Subscript>, H<Subscript>2</Subscript>O: Crystal Structure and IR Spectrum

Abstract  

Crystal structure of Li₂HPO₃,H₂O was determined by single-crystal X-Ray diffraction analysis at 173(2) K. It crystallizes in the monoclinic system (P2_1/c) with the parameters: a = 5.0322(9) ?, b = 8.9795(17) ?, c = 17.088(4) ?, β = 92.672(16)° and Z = 8. The structure was refined to R = 0.0237 and ωR = 0.0650 for 1449 reflexions. The framework of Li₂HPO₃, H₂O can be described as layers perpendicular to the crystallographic c axis. The structure contains two types of Li-tetrahedrons. In one kind each O atom belongs to one HPO₃ group, while in the second kind one apex is an O from water. A network of hydrogen bonds interactions insures the connection between the layers.     

Synthesis and Crystal Structure of 1,7-Bis(4-methoxyphenyl)-4-(1,3-dithiolan-2-ylidene)-1,6-heptadiene-3,5-dione

Abstract  

The synthesis and crystal structure of 1,7-bis(4-methoxyphenyl)-4-(1,3-dithiolan-2-ylidene)-1,6-heptadiene-3,5-dione is described. This compound crystallizes in the space group P2₁ with unit cell parameters a = 14.207 ?, b = 7.752(1) ?, c = 19.473(1) ?, β = 91.00(3)°, with two molecules in the asymmetric unit. The ketenedithioacetal functionality present between the carbonyl groups prevents the possibility of keto-enol tautomerization in this compound. The cinnamoyl groups are organized parallel to each other due to the push–pull nature of the ketenedithioacetal functionality.     

Structural Studies of (Pyridine)<Subscript>3</Subscript>ZnFe(CO)<Subscript>4</Subscript> and (Pyridine)(Neocuproin)CdFe(CO)<Subscript>4</Subscript>

Abstract  

The structure of the previously reported (py)₃ZnFe(CO)₄ (py = pyridine) has been determined, confirming the monomeric nature of this species. The complex has average Zn–N and Zn–Fe bond lengths of 2.0970(7) and 2.4017(3) ?, and features a coordination geometry about Fe which is intermediate between trigonal bipyramidal and face monocapped tetrahedral. The space group is P2₁/c, with a = 8.22080(10) ?, b = 16.1668(3) ?, c = 15.4669(3) ?, β = 102.5869(11)°, V = 2006.21(6) ?³, D_calc. = 1.558 g/cm³ at 150(1) K. A monomeric cadmium analogue, (pyridine)(neocuproin)CdFe(CO)₄, has also been synthesized, and found to possess a similar geometry, with average Cd–N and Cd–Fe bond lengths of 2.352(2) and 2.5380(5) ?. The space group is P[`1] P\overline{1} with a = 10.8900(2) ?, b = 11.3042(3) ?, c = 15.5488(4) ?, α = 85.1251(10)°, β = 84.3468(14)°, γ = 72.0377(15)°, V = 1808.93(7) ?³, D_calc. = 1.478 g/cm³ at 150(1) K.     

Synthesis,Crystal Structure and Thermodynamic Calculations of 1,3-Diethyl-5-(diethylaminium)methylene-2-thiobarbituric Acid Adduct

Abstract  

5-[(Diethylammonio)methyl]-1,3-diethyl-6-oxo-2-thioxo-1,2,3,6-tetrahydro-4-pyrimidinolate (3) was obtained in good yield from the reaction of 1,3-diethyl-6-oxo-5-(1-pyridiniumylmethyl)-2-thioxo-1,2,3,6-tetrahydro-4-pyrimidinolate (2) and diethylamine. The crystal structure of 3 and thermodynamic calculations pertaining to that structure are discussed. The obtained product was characterized using different techniques including single crystal X-ray diffraction, NMR spectroscopy and uni (bi)-molecular systems in gaseous phase. Compound 3 crystallizes in the monoclinic space group P2₁/c with unit cell dimensions a = 13.3701(11) ?, b = 10.9983(7) ?, c = 20.8855(15) ?, β = 105.448(6)°, V = 2960.2(15) ?, Z = 8.     

NH?O and NH?N Hydrogen Bonded Networks in Imidazole-Based Phosphane Oxides: Structures of Tris(2-Isopropylimidazol-4(5)-yl)Phosphane Oxide, Bis(2-Isopropylimidazol-4(5)-yl)Phosphane Oxide and Diphenyl-2-Isopropylimidazol-4(5)-yl Phosphane Oxide

Abstract  

The three title compounds show extensive hydrogen bonding networks in the solid state. The structure of diphenyl-2-isopropylimidazol-4(5)yl phosphane oxide (3) is dominated by N–H⋯OP hydrogen bonds, whereas in bis(2-isopropylimidazol-4(5)-yl)phenyl- (2) and tris(2-isopropylimidazol-4(5)yl)phosphane oxide (1) both, N–H⋯N and N–H⋯OP hydrogen bonds determine the solid-state structures. Compound 1 crystallises in the monoclinic space group Cc with cell parameters a = 19.5447(6) ?, b = 10.45764(16) ?, c = 10.8549(3) ? and β = 121.418(4)°; 2 in the orthorhombic space group Pna2₁, with a = 11.5997(3) ?, b = 9.5836(2) ?, c = 16.1860(4) ? and 3 in the orthorhombic space group Pca2₁, with a = 10.8430(2) ?, b = 10.9277(2) ? and c = 27.7088(6) ?.     

Synthesis and Structural Characterization of K3Th2(PO4)3F2 and RbThPO4F2 as Potential Nuclear Waste Storage Materials

Abstract  

Two new alkali thorium phosphate materials, K₃Th₂(PO₄)₃F₂ and RbThPO₄F₂, were isolated by hydrothermal synthesis at 575 °C. These structures were characterized by single crystal X-ray diffraction using a full-matrix least squares method. The K₃Th₂(PO₄)₃F₂ compound crystallizes in C2/c (No. 15) with a = 15.8179(15) ?, b = 9.8172(8) ?, c = 9.6472(9) ?, β = 121.132(7)°, Z = 4 and R ₁ = 0.0329. This structure contains two large open channels possibly suitable for incorporating radioactive cesium isotopes for waste storage. The RbThPO₄F₂ structure forms in the P2 ₁ /m (No. 11) space group with a = 6.719(4) ?, b = 6.002(3) ?, c = 7.431(5) ?, β = 113.925(19)°, Z = 2 and R ₁ = 0.0359. Unique to this material is a chain of edge sharing thorium with square antiprism coordination environments where fluorine occupies both sites along the edge. Both structures also represent the first occurrences of a fluorinated alkali thorium phosphate material.     

Thermal Expansion of HMX

Abstract  

Thermal expansion of the β-phase of 1,3,5,7-tetranitro-1,3,5,7-tetrazocane (β-HMX, C₄H₈N₈O₈) was studied in the temperature range of −150 to 30 °C. β-HMX is monoclinic (a = 6.5255(10) ?, b = 11.0369(18) ?, c = 7.3640(12) ?, and β = 102.67(1)°), space group P2₁/n. On cooling from room temperature to −150 °C the crystal under goes an anisotropic contraction with the a-axis virtually unchanged while the b and c axes contract by approximately 1.8 and 0.6% respectively. The disproportionate change in the a and c axes results in approximately a 0.4% change in the β angle. Despite the large differences in expansion along the different axes no phase change was observed.     

Synthesis,Characterization and Fluorescent Property of Two Mixed Ligand Coordination Polymers Constructed from 4-Cyclohexene-1,2-dicarboxylate and Nitrogen-Containing Ligands

Abstract  

Two new coordination polymers [Cd(1,2′-cy)(btx)_0.5H₂O]_n 1 and {[Ni(1,2-cy)(2,2′-bipy)(H₂O)₂]·3H₂O}_n 2 (1,2′-cy=4-cyclohexene-1,2-dicarboxylate, btx=1,4-bis(triazol-1-ylmethyl)benzene, 2,2′-bipy=2,2′-bipyridine) had been synthesized. Their structures were characterized by elemental analysis, IR, TG and X-ray single-crystal diffraction analysis. Crystal data for complex 1: Triclinic, space group P-1, a = 6.4303(13) ?, b = 10.399(2) ?, c = 11.713(2), α = 83.04(3)°, β = 81.87(3)°, γ = 83.84(3)°, and Z = 2. For complex 2: Orthorhombic, space group Pbcn, a = 15.613(3) ?, b = 13.970(3) ?, c = 21.290(4) ?, and Z = 4. Complex 1 exhibits an interesting two-dimensional wavelike covalent layer structure. When Ni salt was replaced by Cd salt, and reacts with 1,2′-cy and 2,2′-bipy, one-dimensional chain-like complex 2 was obtained. Furthermore, the fluorescent property of complex 1 was reported.     

Solvothermal Syntheses and Crystal Structures of Two Thiostannates(IV) [M(tepa)]<Subscript>2</Subscript>(<Emphasis Type="Italic">μ</Emphasis>-Sn<Subscript>2</Subscript>S<Subscript>6</Subscript>) (M = Fe<Superscript>2+</Superscript> and Co<Superscript>2+</Superscript>)

Abstract  

Two new thiostannates [M(tepa)]₂(μ-Sn₂S₆) (tepa = tetraethylenepentamine, M = Fe²⁺ 1 and Co²⁺ 2) were prepared by solvothermal method. Compounds 1 and 2 are isostructural. Both the compounds crystallize in the tetragonal system, space group I41/a (no. 88) with the crystal parameters of 1: a = 25.683(2) ?, b = 25.683(2) ?, c = 9.9860(9) ?, V = 6,586.7(11) ?³, Z = 8, and 2: a = 25.742(3) ?, b = 25.742(3) ?, c = 9.8977(12) ?, V = 6,558.5(14) ?³, Z = 8. The Sn₂S₆ ⁴⁻ anion acts as a bidentate bridging ligand connecting two transition metal complex cations by trans terminal S atoms to form neutral centrosymmetric [M(tepa)]₂(μ-Sn₂S₆) moieties.     

Synthesis,Characterization, Crystal and Molecular Structure Analysis of 2,6-Dimethyl-3-Acetyl-5-Carbomethoxy-4-Phenyl-1,4-Dihydropyridine

Abstract  

The synthesis of a novel unsymmetrical dihydropyridine, bearing carboxy methyl and carbomethoxy groups at C(3) and C(5), respectively, has been achieved by applying the modified Hantzsch-type condensation, which involves the Michael addition of Knoevenagel adduct with an enamine. The product obtained was characterized by spectroscopic techniques and finally confirmed by X-ray diffraction studies. The title compound C₁₇H₁₉NO₃ crystallizes in Monoclinic crystal class in space group P2₁/c with cell parameters a = 9.9130(12) ?, b = 7.3320(5) ?, c = 22.018(3) ?, β = 109.637(3)°, V = 1507.2(3) ?³ and Z = 4. The final residual factor R ₁ = 0.0642. The structure exhibits both intra and inter-molecular hydrogen bonding of the type C–H···O and N–H···O. The pyridine ring gives boat conformation.     

Synthesis and X-ray Structure of Acetoxy-4-methyl Phenyl Methyl Acetate

Abstract  

The title compound belongs to acylal class of organic materials and it crystallizes in the monoclinic space group P2₁/c with unit cell parameters a = 7.643(2) ?, b = 20.546(6) ?, c = 7.783 ?, β = 112.206(2)°, V = 1131.50(5) ?³ and Z = 4. The structure has been solved by direct methods and the final R-factor is 0.0401 for 2579 unique reflections. The acetate groups are deviated significantly from the plane of phenyl ring atoms. There are two C–H···O intermolecular hydrogen bonds which gives rise to an antiparallel dimer pattern.     

The Synthesis and Crystal Determination of 3-Hydroxy-4-(4-methoxyphenyl)-5-(2-nitrophenyl)furan-2(5H)-one

Abstract  

The title compound, C₁₇H₁₃NO₆, was synthesized and structurally characterized by elemental analysis, MS, ¹H NMR and single crystal X-ray diffraction. It crystallizes in monoclinic system space group C 2/c with a = 27.981(6) ?, b = 12.996(3) ?, c = 8.0900(16) ?, β = 91.06(3)°, V = 2941.4(10) ?³, Z = 8, R ₁ = 0.0675, wR ₂ = 0.1626, and T = 298(2) K. The X-ray structure determination revealed that the center furanone ring is nearly coplanar with p-methoxybenzene ring and forms a dihedral angle of 87.2(1)° with the nitrobenzene ring. O–H···O Intermolecular hydrogen bonds link pairs of molecules into centrosymmetric dimers, making a graph set motif of R ₂²(10). The dimers are further assembled into a chain of edge-fused R ₄⁴(34) rings running along the [001] direction. The final three-dimensional supramolecular architecture is stabilized by weak π–π interactions.     

Crystal Structure Studies of Two Regioisomers of Bromo-4-Aryloxymethylcoumarins

Abstract  

The 4-(2-bromo-4-methyl-phenoxymethyl)-6-methylcoumarin (1) have been synthesized from bromination of corresponding 4-aryloxymethyl coumarin, which is a regioisomer of 4-(2-bromo-4-methyl-phenoxymethyl)-7-methylcoumarin (2) (CCDC-695895). The compound 1 crystallizes with triclinic space group P-1, a = 8.0943(3) ?, b = 9.3502(3) ?, c = 10.1476(4) ?, α = 90.234(2)°, β = 94.065(2)°, γ = 95.106(2)°, Z = 2 and compound 2 crystallizes with monoclinic space group P2₁/n, a = 8.465(5) ?, b = 13.649(5) ?, c = 13.304(5) ?, α = 90.000(5)°, β = 90.740(5)°, γ = 90.000(5)°, Z = 4. Both the compounds are planar with variation in their intermolecular hydrogen bonds between C–H···O and C–H···π.     

Crystal and Molecular Structures of Two Triazole Derivatives: 4-Cyclopropyl-4,5-dihydro-1H-1,2,3-triazole and Methyl 1-benzyl-1H-1,2,3-triazole-4-carboxylate

Abstract  

The molecule in 4-cyclopropyl-4,5-dihydro-1H-1,2,3-triazole (I) is disposed about a mirror plane with the triazole ring lying in the plane and being orthogonal to the cyclopropyl ring. Considerable delocalization of π-electron density within the triazole ring is indicated by the pattern of bond distances in (I). The molecule of methyl 1-benzyl-1H-1,2,3-triazole-4-carboxylate (II) adopts a curved shape with the dihedral angle formed between the triazole and benzene rings being 63.23(8)°. By contrast to (I), localization of π-electron density within the triazole ring in (II) is indicated. Both (I), via N–H···N hydrogen bonding, and (II), via C–H···O and C–H···N interactions, associate in the solid state to form supramolecular chains. In (I), the chain is a zigzag with a flat topology, whereas in (II) the linear chain has a curved topology. Compound (I) crystallizes in the orthorhombic space group Pnma with a = 5.6470(2) ?, b = 7.3359(4) ?, c = 13.4404(7) ?, and Z = 4. Compound (II) crystallizes in the monoclinic space group P2₁/c with a = 12.1314(5) ?, b = 5.5951(2) ?, c = 16.4339(7) ?, β = 111.269(2)°, and Z = 4.     

Crystal Structure and Conformational Analysis of 4-[(<Emphasis Type="Italic">p</Emphasis>-<Emphasis Type="Italic">N</Emphasis>,<Emphasis Type="Italic">N</Emphasis>-Dimethylamino)Benzylidene]-2-Phenyloxazole-5-One

Abstract  

Molecular and crystal structure of 4-[(p-N,N-dimethylamino)benzylidene]-2-phenyloxazol-5-one, C₁₈H₁₆N₂O₂, have been determined by single crystal X-ray diffraction study. The title compound is monoclinic, with a = 12.1704(23) ?, b = 3.9810(5) ?, c = 30.9603(56) ?, β = 101.176(15)°, Z = 4, D _x = 1.32 g/cm³, μ(Mo Kα) = 0.087 mm⁻¹, and space group is P12₁/c1. The structure was solved by direct methods and refined to a final R = 0.047 for 3166 reflections with I > 2σ(I). The crystal structure is stabilized by C–H⋯O and C–H⋯N type intra-molecular, C–H⋯O type inter-molecular interactions. To enlighten the flexibility and the geometric isomerism (E or Z) of the title compound, the selected torsion angle is varied from −180 to 180° in every 10° separately and molecular energy profile is calculated and analyzed.     

Crystal Structure and Thermodecomposition Kinetics of Mn(II) Complex with 1-Phenyl-3-Methyl-4-Benzoyl-5-Pyrazolone

Abstract  

The complex [Mn(PMBP)₂(CH₃OH)₂] of manganese(II) with 1-phenyl-3-methyl- 4-benzoyl-5-pyrazolone (PMBP) was prepared and characterized by elemental analysis, thermal analysis, IR. The crystal structure of the complex determined by single crystal X-ray analysis, indicates that PMBP is a bidentate ligand in the complex and Mn(II) atom is six-coordinated and is in a meridional octahedral environment. The compound crystallizes in the monoclinic system, space group P ₂(1)/c, with a = 11.038(10) ?, b = 16.254(15) ?, c = 9.540(9) ?, α = 90.00°, β = 105.112(10)°, γ = 90.00°, V = 1,652(3) ?³, D _x  = 1.354 g cm⁻³ and Z = 2. The thermal decomposition kinetics of the complex was investigated under nonisothermal conditions using the Achar differential method and the Coats–Redfern integral method.