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1.
Bis(acetylacetonato)oxovanadium C10H14O5V (I) and (S)-[2-(N-salicylidene)aminopropionate]oxovanadium monohydrate C10H9NO5V (II) are synthesized. The crystal structures of compounds I and II are determined using single-crystal X-ray diffraction. Crystals of compound I are triclinic, a = 7.4997(19) Å, b = 8.2015(15) Å, c = 11.339(3) Å, α = 91.37(2)°, β = 110.36(2)°, γ = 113.33(2)°, Z = 2, and space group \(P\bar 1\). Crystals of compound II are monoclinic, a = 8.5106(16) Å, b = 7.373(2) Å, c = 9.1941(16) Å, β = 101.88(1)°, Z = 2, and space group P21. The structures of compounds I and II are solved by direct methods and refined to R1 = 0.0382 and 0.0386, respectively. The oxovanadium complexes synthesized are investigated by vibrational spectroscopy.  相似文献   

2.
The crystal structures of [(cys-syn-cys-dicyclohexano-18-crown-6 · H3O)][TaF6] and [(cys-syn-cys-dicyclohexano-18-crown-6 · H3O)][NbF6] complex compounds are determined using X-ray diffraction analysis. The tantalum complex has two polymorphic modifications, namely, the monoclinic (I) and triclinic (II) modifications. The unit cell parameters of these compounds are as follows: a = 8.507(4) Å, b = 11.947(5) Å, c = 27.392(12) Å, β = 93.11(1)°, Z = 4, and space group P21/n for modification I; and a = 10.828(1) Å, b = 11.204(1) Å, c = 12.378(1) Å, α = 72.12(1)°, β = 79.40(1)°, γ = 73.70(1)°, Z = 2, and space group P-1 for modification II. The triclinic niobium complex [(cys-syn-cys-dicyclohexano-18-crown-6 · H3O)][NbF6] (III) with the unit cell parameters a = 10.796(3) Å, b = 11.183(3) Å, c = 12.352(3) Å, α = 72.364(5)°, β = 79.577(5)°, γ = 73.773(4)°, Z = 2, and space group P-1 is isostructural with tantalum complex II. The structures of all three complexes are ionic in character. The oxonium cation in complexes I–III is encapsulated by the crown ether and thus forms one ordinary and two bifurcated hydrogen bonds with the oxygen atoms of the crown ether. This macrocyclic cation is bound to the anions through the C-H...F contacts (H...F, 2.48–2.58 Å). The conformation of the macrocycle in complex I differs substantially from that in complex II (III).  相似文献   

3.
The crystal structure of a supramolecular system consisting of indole-2,3-dione 1-(2-oxopropyl)-3-ethylene ketal (I) and indole-2,3-dione 1-(2-oxopropyl)-3-ethylene ketal thiosemicarbazone (II) molecules that are linked together by hydrogen bonds is determined using X-ray diffraction. The crystal is monoclinic, and the unit cell parameters are as follows: a = 12.8360(3) Å, b = 10.7330(3) Å, c = 19.4610(3) Å, β = 99.566(1)°, space group P21/c, and Z = 4 (C27H29N5O7S). In molecules I and II, the indole-2,3-dione 3-ethylene ketal fragments have a virtually identical structure. The pyrrole and dioxolane fragments are spiro-linked through the carbon atom with a dihedral angle close to 90°. The adjacent pyrrole and benzene rings are coplanar to within 4.4°. In molecule II, the oxygen atom of the dioxolane fragment and the terminal nitrogen atom of the thiosemicarbazide fragment are involved in the N-HïO intramolecular hydrogen bond [3.294(2) Å]. The key role in the formation of the crystal structure is played by intermolecular hydrogen bonds of the N-H?dO, C-H?O, C-H?N, and N-H?S types.  相似文献   

4.
The synthesis and single-crystal X-ray diffraction study of Cs[UO2(SeO4)(OH)] · 1.5H2O (I) and Cs[UO2(SeO4)(OH)] · H2O (II) are performed. Compound I crystallizes in the monoclinic crystal system, a = 7.2142(2) Å, b = 14.4942(4) Å, c = 8.9270(3) Å, β = 112.706(1)°, space group P21/m, Z = 4, and R = 0.0222. Compound II is monoclinic, a = 8.4549(2) Å, b = 11.5358(3) Å, c = 9.5565(2) Å, β = 113.273(1)°, space group P21/c, Z = 4, and R = 0.0219. The main structural units of crystals I and II are [UO2(SeO4)(OH)]? layers which belong to the AT 3 M 2 crystal chemical group of uranyl complexes (A = UO 2 2+ , T 3 = SeO4 2?, and M 2 = OH?). In structure I, johannite-like layers are found. Structure II is a topological isomer of I. The two structures differ in the number of U(VI) atoms bound to the central atom by all bridging ligands.  相似文献   

5.
The crystal structures of dimethyl 4-phenylthiosemicarbazidediacetate C13H17N3O4S (I) and its adduct [C8H12O8Rh2 (C13H17N3O4S)2] (II) with rhodium(II) acetate are determined by X-ray diffraction analysis. The unit cell parameters of crystals I are as follows: a = 8.066(6) Å, b = 15.812(6) Å, c = 24.977(8) Å, β = 94.88(3)°, space group P21/n, and Z = 8. The unit cell parameters of crystals II are a = 8.513(1) Å, b = 16.055(1) Å, c = 16.071(3) Å, β = 104.99(1)°, space group P21/c, and Z = 2. In structure I, two crystallographically independent molecules considerably differ from each other in the mutual orientation of the structural fragments containing the ester groups. In the centrosymmetric dimeric complex II, the organic molecule I acts as a monodentate thio ligand and adopts only one conformation.  相似文献   

6.
1-[(E)-2-(4-bromophenyl)-1-diazenyl]-3-({3-[(E)-2-(4-bromophenyl)-1-diazenyl]-6-ethylhexahydro-1-pyrimidinyl}methyl)-4-ethylhexahydropyrimidine (1) has been synthesized by reaction of a mixture of formaldehyde and 1,3-pentanediamine{DYTEK®EPdiamine} with p-bromobenzenediazonium chloride. This compound crystallizes in two polymorphic forms 1-α and 1-β whose crystal structures have been determined by single crystal X-ray diffraction analysis. Both polymorphs 1-α and 1-β display crystallographic disorder within the hexahydropyrimidine rings. The molecule of 1 is built up of two equivalent 3-(aryldiazenyl)-6-ethylhexahydro-1-pyrimidinyl groups in the s-trans orientation around the central methylene group (C13). In both structures the triazene moieties adopt the anti configuration around the N=N bonds, displaying significant π-conjugation. The crystal packings are determined only by van der Waals interactions. The crystal structures of 1-α and 1-β are compared with the previously reported structure of the 5,5-dimethylhexahydropyrimidine analogue 3. Compounds 1 and 3 are isomeric with respect to the hexahydropyrimidine moiety. The structures of 1 and 3 are very different in one respect; in 1 the aryldiazenyl-hexahydropyrimidinyl groups are in the s-trans orientation around the central methylene group, whereas in 3 the arrangement of the aryldiazenylhexahydropyrimidinyl groups is the s-cis orientation. Crystal data: 1-α C25H34N8Br2, monoclinic, space group P2(1)/c, a = 9.2150(3), b = 19.4059(6), c = 15.4324(5) Å, β = 98.738(1)°, V = 2727.7(2) Å3, for Z = 4; 1-β C25H34N8Br2, triclinic, space group P-1, a = 9.6009(3), b = 10.7509(4), c = 14.2169(5) Å, α = 99.830(2), β = 105.973(3), γ = 95.578(1)°, V = 1373.9(1) Å3, for Z = 2.  相似文献   

7.
The structure of 2,4,6-triisopropylbenzenesulfonyl chloride (TPSCl) (I) was studied by X-ray diffraction. Compound I is a highly selective condensing agent first suggested by Khorana for the formation of the C3′–C5′ interribonucleotide linkage in the oligo- and polyribonucleotide synthesis. I crystals are orthorhombic. At ?120°C, the unit-cell parameters are a = 14.184(4) Å, b = 11.344(5) Å, c = 19.883(6) Å, V = 3199(2) Å3, d calc = 1.257 g/cm3, Z = 8, sp. gr. Pbca. Molecule I adopts a strongly flattened boat conformation with the carbon atoms C-SO2Cl (C 1) and C-i-Pr (C4) of the benzene ring deviating from the bottom of the boat by 0.065(1) and 0.032(1) Å, respectively. Molecule I is sterically overcrowded, resulting in an increase in the bond lengths and bond-angle distortions in the fragment containing the SO2Cl group and two ortho-i-Pr groups. Nonbonded contacts that are present in the molecule can be considered weak intramolecular hydrogen bonds (for example, the (CH3)2C-H?O=S bond). There is no rotation of the SO2Cl, ortho-i-Pr, and CH3 groups. The above-mentioned facts are, apparently, responsible for the specific selectivity of TPSCl. New readily available sterically hindered arenesulfonyl chlorides were designed.  相似文献   

8.
Five derivatives of curcumin analogue (R = OCH2CH3 (1), R = N(CH3)2 (2), R = 2,4,5-OCH3 (3), R = 2,4,6-OCH3 (4), and R = 3,4,5-OCH3 (5)) were synthesized and characterized by 1H NMR, FT-IR and UV–Vis spectroscopy. The synthesized derivatives were screened for antityrosinase activity, and found that 4 and 5 possess such activity. The crystal structure of 1 was determined by single crystal X-ray diffraction: monoclinic, sp. gr. P21/c, a = 17.5728(15) Å, b = 5.9121(5) Å, c = 19.8269(13) Å, β = 121.155(5)°, Z = 4. The molecule 1 is twisted with the dihedral angle between two phenyl rings being 15.68(10)°. In the crystal packing, the molecules 1 are linked into chains by C?H···π interactions and further stacked by π···π interactions with the centroid–centroid distance of 3.9311(13) Å.  相似文献   

9.
The crystal structures of two terpene derivatives, 2,4,5,6,7,7a-hexahydro-7a-hydroxy-3,6-dimethyl-2-benzofuranone (compound I) and β-cyclolavandulic acid (compound II), were determined by single-crystal diffractometry. Compound I, C10H14O3, crystallizes in the orthorhombic space group P212121 with the unit cell parameters a = 6.715(1) Å, b = 7.043(1) Å, c = 20.292(3) Å, and Z = 4. The six-membered ring has an ideal chair conformation. The five-membered ring is planar. Compound II, C10H16O2, crystallizes in the monoclinic space group P21/n with the unit cell parameters a = 8.446(1) Å, b = 12.156(1) Å, c = 9.901(1) Å, β = 106.29(1)°, and Z = 4. The cyclohexene ring exhibits a half-chair conformation. Both the crystal structures are stabilized by intermolecular O-H?O hydrogen bonds.  相似文献   

10.
The compounds 5(2-thienyl)-and 5(3-thienyl)-dipyrromethane (1 and2, respectively) have been synthesized and isolated from the acid-catalyzed reaction between thiophenes-carboxaldehyde and pyrrole. Characterization by X-ray diffraction confirms molecular structures involving twoortho-substituted pyrrolyl and one thienyl groups. Both the compounds1 and2 were crystallized in the monoclinic space groupP21/n with cell parametersa = 5.7149(16) Å,b = 17.338(6) Å, andc = 11.785(4) Å, β = 98.466(9)°,V = 1155.0(6) Å3 for compound1; anda = 5.828(4) Å,b = 17.424(10) Å,c = 11.822(8) Å, β = 98.10(2)°, andV = 1188.4(13) Å3 for compound2.  相似文献   

11.
The crystal structures of two organosilicon compounds are studied by X-ray diffraction. Crystals of trans-2,8-dihydroxy-2,4,4′,6,6′,8,10,10′,12,12′-decamethyl-5,11-dicarbacyclohexasiloxane, C12H36O6Si6, (I) are studied at 293 K [a = b = 16.310(4) Å, c = 9.849(3) Å, V = 2620(1) Å3, dcalcd = 1.128 g/cm3, space group P4(2)/n, Z = 4, 3370 reflections, wR2 = 0.1167, R1 = 0.0472 for 2291 reflections with F > 4σ(F)]. Crystals of trans-1,4-dihydroxy-1,4-dimethyl-1,4-disilacyclohexane, C6H16O2Si2, (II) are studied at 110 K [a = 6.8253(5) Å, b = 9.5495(8) Å, c = 12.0064(10) Å, α = 101.774(2)°, β = 102.203(2)°, γ = 95.068(2)°, V = 741.8(1) Å3, dcalcd = 1.184 g/cm3, space group \(P\bar 1\), Z = 3, 6267 reflections, wR2 = 0.1052, R1 = 0.0421 for 3299 reflections with F > 4σ(F)]. It is found that the conformation of the ring in compound I, which contains two methylene groups in the cyclohexasiloxane ring, differs from those in its analogues containing only oxygen atoms or one methylene group in the ring. The noticeable difference between the SiCSi angle [123.0(2)°] and the tetrahedral angle is characteristic of cyclohexasiloxanes. Structure II contains three independent molecules with very close conformations. The cyclohexane rings adopt a chair conformation. The methylene groups in II, in distinction to those in I, are characterized by a standard tetrahedral coordination.  相似文献   

12.
The copper(II) phthalate complex with nicotinamide [CuL 2(μ-Pht)(H2O)] · 0.5H2O(I) (where L is nicotinamide and Pht 2? is an anion of phthalic acid) is synthesized and investigated using IR spectroscopy and X-ray diffraction. The crystals of compound I are monoclinic, a = 13.368(2) Å, b = 7.891(3) Å, c = 20.480(2) Å, β = 108.69(2)°, Z = 4, and space group P21/c. The structural units of crystal I are linear chains formed by bridging phthalate anions and crystallization water molecules. The copper atom is coordinated by two pyridine nitrogen atoms of two nicotinamide ligands (Cu-N, 2.001 and 2.045 Å), two oxygen atoms of different phthalate anions (Cu-O, 1.964 and 2.235 Å), and the oxygen atom of the H2 O molecule (Cu-O, 2.014 Å). The coordination polyhedron of the copper atom is completed to an elongated (4 + 1 + 1) tetragonal bipyramid by the second (chelating) oxygen atom of the carboxyl group (Cu-O, 2.587 Å), which is one of the anions of phthalic acid. The linear polymer molecules are joined into complex macromolecular dimers with the closest internal contacts of the specific type. The macromolecular dimers are the main supramolecular ensembles of the crystal structure.  相似文献   

13.
Two isostructural complexes of dioxonium [H5O2]+ with tetrabenzo-30-crown-10 of the compositions [(tetrabenzo-30-crown-10 · H5O2)][TaF6] (I) and [(tetrabenzo-30-crown-10 · H5O2)][NbF6] (II) are studied using X-ray diffraction. The complexes crystallize in the monoclinic crystal system (space group C2/c, Z = 4). The unit cell parameters of these compounds are as follows: a = 15.6583(12) Å, b = 15.2259(13) Å, c = 16.4473(13) Å, and β = 99.398(6)° for complex I and a = 15.7117(12) Å, b = 15.2785(15) Å, c = 16.5247(15) Å, and β = 99.398(7)° for complex II. These complexes belong to the ionic type. The dioxonium cation [H5O2]+ in the form of the two-unit cluster [H3O · H2O]+ is stabilized by the strong hydrogen bond OH?O [O?O, 2.353(4) Å] and encapsulated by the crown ether. Each oxygen atom of the dioxonium cation also forms two oxygen bonds O?O(crown). The crown ether adopts an unusual two-level (pocket-like) conformation, which provides a complete encapsulation of the oxonium associate. The interaction of the cationic complex with the anion in the crystal occurs through contacts of the C-H?F type.  相似文献   

14.
(4E)-5-(3-Chlorophenyl)-N-(4-chlorophenyl)-2-diazo-3-oxopent-4-enoic acid amide (5) was synthesized from p-chloroaniline to N-(4-chlorophenyl)-2-diazo-3-oxo-butyramide (4) with 3-chlorobenzaldehyde. The yielded product 5 was investigated with X-ray crystallographic, NMR, MS, and IR techniques. Compound 5 (C17H11Cl2N3O2, Formula wt = 360.19), crystallizes in the monoclinic space group P21/c with unit cell parameters a = 10.516(2), b = 17.996(4), c = 8.902(2) Å, α = 90.00, β = 105.36(3), γ = 90.00°. V = 1624.5(6) Å3, Z = 4, D x = 1.473 Mg m?3. The final R was 0.0511.  相似文献   

15.
A series of chalcone podands with the propenone group in the ortho position of the bridging aryl substituent with respect to the oxyethylene fragment is synthesized. The influence of the preorganization of the chalcone podand molecules in crystals on their ability to participate in topochemical reactions is investigated. From analyzing the X-ray structural data, the highest probability of the solid-state photochemical [2 + 2]cycloaddition is predicted for podands with phenyl substituents and the oxyethylene fragment containing two or three oxygen atoms. The X-ray structural data for the chalcone podand C32H26O4 (3a) are as follows: a = 7.904(9) Å, b = 14.92(2) Å, c = 21.30(3) Å, β = 91.7(1)°, monoclinic system, space group P21/c, Z = 4, V = 2510(5) Å3, ρ = 1.26 g/cm3, and R = 0.046; C34H30O5 (3b): a = 15.738(9) Å, b = 11.889(2) Å, c = 15.0830(15) Å, β = 105.47(14)°, monoclinic system, space group C2/c, Z = 4, V = 2720.0(9) Å3, ρ = 1.266 g/cm3, and R = 0.0418; C32H24N2O8 (4a): a = 17.9416(18) Å, b = 10.9703(8) Å, c = 41.699(2) Å, β = 105.970(11)°, monoclinic system, space group P21/c, Z = 4, V = 2781.4(5) Å3, ρ = 1.348 g/cm3, and R = 0.0426; C36H32N2O10 (4c): a = 7.6286(5)Å, b = 17.9398(10) Å, c = 11.5890(3)Å, β = 95.287(4)°, monoclinic system, space group P21/n, Z = 2, V = 1579.27(14) Å3, ρ = 1.372 g/cm3, and R = 0.0377; and C28H22O6 (5a): a = 15.6032(10) Å, b = 8.1131(5) Å, c = 17.7334(11) Å, β = 91.381(5)°, monoclinic system, space group C2/c, Z = 4, V = 2244.2(2) Å3, ρ = 1.345 g/cm3, and R = 0.0309.  相似文献   

16.
TheNd4.5Pb1.7(VO4)0.3(BO3)O6.42(I), Tb4.5Pb1.6(GeO4)0.4(BO3)O6.02(II), Dy4.5Pb1.68(GeO4)0.32(BO3)O6.28(III), and Ho8.66(BO3)2(B2O5)O8(IV) crystals were grown by spontaneous crystallization from flux and studied by the methods of X-ray diffraction analysis. The unit-cell parameters are a = 21.946, 21.590, 21.478, and 18.207 Å; b = 3.7881, 3.6565, 3.6333, and 3.6685 Å; c = 16.857, 16.618, 16.544, and 14.024 Å; β = 123.70°, 124.64°, 124.49°, and 119.81°; sp. gr. C2/m; and Z = 4, 4, 4, and 2 for I, II, III, and IV, respectively. In I–III compounds, Pb atoms, together with the atoms of group V, and Pb atoms and Ge atoms occupy the mixed positions. In structure IV, all the five independent Ho positions are occupied only partially.  相似文献   

17.
Manganese(II) 9-molybdocobaltate(III) of the composition [Mn(H2O)4] · [CoMo9O27(OH)5] · 7H2O (I) has been synthesized for the first time and investigated using X-ray diffraction and thermal gravimetric analyses. Compound I crystallizes in the trigonal system with the following unit cell parameters: a = 15.926(1) Å, c = 12.363(1) Å, V = 2715.6(4) Å3, M = 1692.55, Z = 3, ρ(calcd) = 3.105 g/cm3, space group R32.  相似文献   

18.
Six 3-substituted hydrazone derivatives [R = ?OCH3 (1), ?NH2 (2), ?NO2 (3), ?F (4), ?Cl (5), and ?Br (6)] were synthesized by condensation reaction. Their structures were elucidated by 1H NMR, FT-IR and UV-Vis spectroscopy. The synthesized compounds were further evaluated for their α-glucosidase inhibitory activity. Strong activity was found for 1 and 3. The crystal structure of 1 was determined by single crystal X-ray diffraction: a = 6.9743(1) Å, b = 18.3627(3) Å, c = 12.0207(2) Å, β = 96.087(1)o, sp. gr. P21/c, Z = 4. The molecule of 1 is twisted with the dihedral angle between the two phenyl rings being 51.91(4)°. In the crystal packing, the molecules are linked into chains by C–H···π interactions.  相似文献   

19.
The bromination reaction of 1,2,3,4-tetrahydro-1,10-phenanthroline (tphen) is investigated, which can afford a new heterocyclic compound, namely 6-bromo-1,2,3,4-tetrahydro-1,10-phenanthroline (1). The bromide salt of 1, i.e., 1 · (1H) · Br (2), can be isolated from the bromination system. The accurate structures of both compounds are confirmed and investigated by single-crystal X-ray diffraction. The result proves that the bromination reaction of tphen mainly affords its C6-substituted product. In compounds 1 and 2, the N?H···Br hydrogen bonds play an important role in intermolecular connection. Crystal data of 1: Monoclinic system, sp. gr. Pc, a = 4.6628(8) Å, b = 8.7980(15) Å, c = 13.1347(19) Å, β = 101.342(5)°, Z = 2, V = 528.31(15) Å3. Crystal data of 2: Monoclinic system, sp. gr. P21/n, a = 16.6171(16) Å, b = 7.8323(8) Å, c = 18.6972(18) Å, β = 113.597(2)°, Z = 4, V = 2230.0(4) Å3.  相似文献   

20.
The crystal structures of bis{4-bromo-2-[(2-hydroxyethylimino)methyl]phenolato}copper (I) and bis{4-chloro-2-[(2-hydroxyethylimino)methyl]phenolato}copper (II) are determined. Crystals I are monoclinic, space group P21/c, Z = 2, and R = 0.0732 (for all reflections). Crystals II are likewise monoclinic, space group P21/n, Z = 2, and R = 0.1106. In the structures of compounds I and II, the metal atom is situated at the center of symmetry and coordinated by two singly deprotonated bidentate 4-bromo-or 4-chloro-2-[(2-hydroxyethylimino)methylphenol molecules, respectively, through phenol oxygen and azomethine nitrogen atoms, which form a distorted planar square. In the structures of compound II, the coordination polyhedron of the central atom is completed to an elongated tetragonal bipyramid by the amino alcohol oxygen atoms of the adjacent complexes.  相似文献   

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