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1.
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) Å3, 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) Å3, 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) Å3, 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) Å3, 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.  相似文献   

2.
Abstract Crystal structures for the isomeric compounds benzyl-(2-chloro-6-methylpyrimidin-4-yl)amine (1), as its hemi-hydrate, and benzyl-(4-chloro-6-methylpyrimidin-2-yl)amine (2) have been determined. Conformational differences lead to multiple molecules, i.e. two and three, in their respective structures. Layers feature in each of the crystal structures and are stabilized by substantial hydrogen-bonding interactions. Compound (1) crystallizes as a hemi-hydrate in the triclinic space group P-1 with a = 8.667(5) ?, b = 11.421(7) ?, c = 12.954(8) ?, α = 78.330(10)°, β = 84.553(10)°, γ = 75.510(9)°, and Z = 4. Compound (2) crystallizes in the monoclinic space group P21/c with a = 10.740(3) ?, b = 21.487(6) ?, c = 14.914(4) ?, β = 95.014(5)°, and Z = 12. Index Abstract Substantial hydrogen-bonding interactions leading to layer structures feature in each of the crystal structures of the isomeric title compounds. Electronic supplementary material The online version of this article (doi: ) contains supplementary material, which is available to authorized users.  相似文献   

3.
Abstract  The reaction of phosphine ligand endo,endo-2,3-bis(diphenylphosphinomethyl)-5-norbornene (dpmn) with PtCl2(cod) and PtMe2(cod) yields PtCl2(dpmn) (2) and PtMe2(dpmn) (4), respectively. Treatment of 2 with excess MeLi or MeMgCl also furnishes 4 in good yield. Both new platinum compounds have been isolated and characterized by NMR spectroscopy (1H and 31P), elemental analyses, and X-ray crystallography. 2 Crystallizes, as the CH2Cl2 solvate, in the orthorhombic space group Pnma, a = 18.062(3) ?, b = 16.602(3) ?, c = 11.088(2) ?, V = 3,324.7(9) ?3, Z = 4, D cacl = 1.681 mg/m3; R = 0.0432, R w = 0.0759 for 3,755 observed reflections with I > 2σ(I). 4 Crystallizes, as the CH2Cl2 solvate, in the orthorhombic space group Pnma, a = 17.969(3) ?, b = 16.689(3) ?, c = 11.237(2) ?, V = 3,370(1) ?3, Z = 4, D cacl = 1.610 mg/m3; R = 0.0268, R w = 0.0665 for 4,098 observed reflections with I > 2σ(I). The solid-state structures of 2 and 4 confirm the coordination of the platinum(II) center by the seven-membered chelating dpmn ligand; 2 and 4 represent the first structurally characterized examples of organometallic compounds based on the endo,endo-2,3-bis(diphenylphosphinomethyl)-5-norbornene ligand. Graphical Abstract  The new platinum(II) compounds PtCl2(dpmn) (2) and PtMe2(dpmn) (4) have been synthesized, and their structures established by NMR spectroscopy (1H and 31P) and X-ray crystallography. Compounds 2 and 4 are the first structurally characterized examples of organometallic compounds containing the endo,endo-2,3-bis(diphenylphosphinomethyl)-5-norbornene (dpmn) ligand.
Michael G. Richmond (Corresponding author)Email:
  相似文献   

4.
N 1-acetylacetamidrazones and N 1-benzoylacetamidrazones (1a–d) were characterized by 1H and 13C NMR spectroscopy. The actual tautomeric form present has been shown to be the amide hydrazone. NMR spectra of N 1-acetylacetamidrazones (1a,b) showed the existence of Z and E isomers in solution, while N 1-benzoylacetamidrazones (1c,d) were present as Z isomers. The crystal structures of the amidrazones have been determined at 173 and 293 K, respectively. The amidrazones 1c and 1d crystallize in the monoclinic system: in particular for 1c space group P21/c, with a = 11.016(5), b = 20.594(14), c = 13.657(7) Å = 98.29(3)° V = 3066(3) Å3 and D c = 1.243 g/cm3 for Z = 4; for 1d space group P21/a, with a = 9.410(5), b = 10.449(3), c = 14.295(11) Å = 101.04(5)° V = 1380(1) Å3 and D c = 1.220 g/cm3 for Z = 4. The X-ray diffraction analysis carried out on 1c has shown the presence of three molecules in the asymmetric unit which differ for the orientation of the phenyl ring.  相似文献   

5.
Abstract Metronidazole (MET-OH), widely used as an antibacterial agent, is found to have some side effects on human bodies. Due to these disadvantages, people have been looking for its modification compounds for substituents. In this article, four MET-OH derivatives were designed, prepared, and structurally characterized by single crystal X-ray diffraction. These compounds are MET-OTs (1), MET-Br (2), MET-Cl (3), and MET-I (4). X-ray structure analyses revealed that, 1 crystallized in the monoclinic system with space group P2 1 /c, with a = 16.1178, b = 7.5473, c = 13.4161 ?, V = 1520.3 ?3, β = 111.3210o and Z = 4. 2 crystallized in the monoclinic system with space group P2 1 /c, with a = 12.079, b = 11.089, c = 6.380 ?, V = 847.1 ?3, β = 97.57o and Z = 4. 3 crystallized in the monoclinic system with space group P2 1 /c, with a = 12.098, b = 11.007, c = 6.295 ?, V = 830.3 ?3, β = 97.886o and Z = 4. 4 crystallized in the triclinic system with space group P1, with a = 6.192, b = 7.740, c = 10.001 ?, V = 457.9 ?3, α = 89.073, β = 86.903, γ = 73.097o and Z = 2. Index Abstract In this article, metronidazole-derived compounds were prepared and structurally characterized by single crystal X-ray diffraction   相似文献   

6.
Abstract The crystal structures of two unsolvated hexameric complexes and one N,N,N,N′-tetramethyl-1,2-ethanediamine (TMEDA)-solvated dimeric complex of the lithium enolate of 2-methyl-1-phenyl-1-propanone (lithioisobutyrophenone, LiIBP) are reported. The unsolvated LiIBP complexes crystallize from benzene-d 6 to yield two different types of crystals that have similar structures: one in the triclinic space group P-1 with a = 10.7944(7), b = 11.9350(8), c = 12.0956(8) ?; α = 117.5560(10), β = 100.8090(10), γ = 92.3030(10)° and Z = 1 and a second in the monoclinic space group C2/c with a = 17.6011(11), b = 14.7389(9), c = 21.0943(13) ?; β = 105.2510(10)° and Z = 4. The two LiIBP hexamers differ slightly in the conformations of the enolate moieties around the Li6O6 core. The hexamer in both the triclinic as well as the monoclinic polymorph is located on a crystallographic inversion center that each generates the other half of the cluster. The TMEDA-solvated LiIBP dimer crystallizes from hexanes in the monoclinic space group C2/c with a = 11.8472(6), b = 14.8268(7), c = 19.2719(9) ?; β = 98.8480(10)° and Z = 4. The center of the dimer is located on a crystallographic C2 axis. These complexes represent only the second reported crystal structures of either an unsolvated hexamer or a solvated dimer of a lithium enolate of a simple monocarbonyl ketone. Graphical Abstract The X-ray crystal structures of two unsolvated hexameric and one N,N,N,N′-tetramethyl-1,2-ethanediamine (TMEDA)-solvated complexes of the lithium enolate of 2-methyl-1-phenyl-1-propanone (lithioisobutyrophenone, LiIBP) are reported. Electronic supplementary material The online version of this article (doi: ) contains supplementary material, which is available to authorized users.  相似文献   

7.
Abstract  The crystal structures of 1,2-bis-{(2-aminobenzoyl-)amino}ethane(1), 1,4-bis-{(2-aminobenzoyl-)amino}butane(2) and 2,2-dimethyl-1,3-bis-{(2-aminobenzoyl-)amino}-propane(3) have been determined by single crystal X-ray diffraction analysis. 1 and 2 are centrosymmetric molecules which lie on crystallographic centers of symmetry and adopt extended conformations. On the other hand, owing to the odd number of carbon atoms in the spacer unit, 3 does not show centrosymmetry, but crystallizes in a non-centrosymmetric space group and assumes a folded conformation. The crystal structures of 1, 2 and 3 are compared with the known structures of anthranilamide (7) and the N-alkyl anthranilamide derivative 8. Crystal data: 1 C16H18N4O2, monoclinic, space group P21/a, a = 9.5262(8) ?, b = 5.4200(5) ?, c = 15.3821(14) ?, β = 105.980(5)° and V = 763.52(12) ?3, for Z = 2. 2 C18H22N4O2, monoclinic, space group C2/c, a = 32.0710(17) ?, b = 5.4732(4) ?, c = 9.7326(5) ?, β = 102.570(4)° and V = 1667.42(17) ?3, for Z = 4. 3 C19H24N4O2, orthorhombic, space group Pca21, a = 16.7676(4) ?, b = 10.1847(2) ?, c = 10.5338(5) ?, and V = 1798.89(7) ?3, for Z = 4. Index Abstract  The crystal structures of 1,2-bis-{(2-aminobenzoyl-)amino}ethane(1), 1,4-bis-{(2-aminobenzoyl-)amino}butane(2) and 2,2-dimethyl-1,3-bis-{(2-aminobenzoyl-)amino}-propane(3) have been determined by single crystal X-ray diffraction analysis. 1 and 2 are centrosymmetric molecules which lie on crystallographic centers of symmetry and adopt extended conformations, whereas 3 does not show centrosymmetry, but crystallizes in a non-centrosymmetric space group and assumes a folded conformation.   相似文献   

8.
The X-ray crystal structure of benzimidazolium dichromate is determined. The compound C14H14Cr2N4O7 is Triclinic in P-1 with a = 8.2722(8) Å, b = 10.0269(10) Å, c = 11.7001(11) Å, = 102.073(2)°, =100.483(2)°, = 67.288(2)°, V = 869.88(15) Å3, D calc = 1.734 g/cm3, and Z = 2. A dichromate ion connects two benzimidazolium rings via hydrgen bonds, as leads to face-to-face intramolecular aromatic stacking. The major force of crystal formation comes from hydrogen bonds, and an intermolecular hydrogen bridge is formed to connect two neighbored dichromate ions.  相似文献   

9.
L-arginine fluoride is a promising compound that exhibits nonlinear optical properties. It efficiently converts two single photons of the same polarization and frequency to one photon of frequency 2 (type I phase matching). C6H15N4O2 +F is monoclinic, space group P21, a = 5.4475(4) Å, b = 8.5133(6) Å, c = 10.2195(7) Å, = 93.475(6)°. The cation has a zwitterionic form, protonated at both the guanidyl and amino groups. The arginine C atom is in a trans position to the carboxyl group. A complex three-dimensional hydrogen bond network links the anions and cations together.  相似文献   

10.
Crystal structural studies of two new biisoquinoline derivatives, a neutral compound C20H24N2 (3) and a salt C18H21N2 +C10H14BrO4S H2O (4) are described and discussed. Compound 3 crystallizes in the monoclinic space group P2 1/c, with a = 11.039(2), b = 7.791(2), c = 19.001(4) Å, = 104.31(3)°, and Z = 4. Compound 4 crystallizes in the monoclinic space group P2 1, with a = 12.0021(3), b = 8.9189(2), c = 12.8685(4) Å, = 100.7600(10)°, and Z = 2. The absolute stereochemistry of 4 in the solid state has been determined. The biisoquinoline rings in both compounds adopt twist-boat conformations with significant deviations from ideal geometry. The two heterocyclic rings in each species are oriented so that they are not overlayed with each other and the phenyl rings are oppositely directed. The cations and the anions in 4 are linked together through an elaborate system of hydrogen bonding involving the water molecule.  相似文献   

11.
We have crystallized the 2,6-distyrylpyridine compound from the condensation reaction of the 2,6-dimethylpyridine with benzaldehyde (at 135°C) to obtain a model compound having three rings joined with two double bonds in order to understand the structure of poly(2,6-styrylpyridine) and poly(2,6-pyridinediylvinylene) and their formation mechanism. The X-ray structure shows that the title compound belongs to the trigonal crystal system, space group P32, and with unit cell dimensions a = 15.5637 (12) Å, c = 5.7852 (13) Å. From the molecular structure it was clear that the substituents on double bonds were in the trans position, which was in agreement to the IR and 1H NMR results. The molecule is planar and forms stacks in the crystal. The molecular structure of 2,6-distyrylpyridine has two trans double bonds between the rings and therefore it can be in three nonequivalent conformations. The preferred conformation showed by X-ray crystallography can be the result of weak steric interactions between the double bond trans hydrogens and the nearby hydrogens of the phenyl or pyridyl groups. The crystal structure, and IR and 1H NMR results are currently reported.  相似文献   

12.
The title compound, o-methacryloylaminophenylarsonic acid (o-MAPHA), C10H12AsNO4, is a monomer used to obtain water-soluble polyelectrolytes. It was obtained from the condensation reaction of o-arsanilic acid and methacryloyl chloride. Crystallization from aqueous ethanol solution yielded colorless prismatic crystals, and one was used for X-ray analysis. The crystal structure was solved using direct methods with a refined R 1 = 0.0483. The crystal structure belongs to the triclinic system, space group , and the asymmetric unit comprises two molecules of the o-MAPHA acid and one water molecule. Both acid molecules are approximately planar and in both molecules the As atom presents common tetrahedral geometry with two long As–O bonds for hydroxyl groups and one short As–O bond for the oxo groups. The structure of o-arsanilic acid (o-ARSA), C6H8AsNO3, was also determinated using the same methods and compared with the o-arsanilic acid structure previously reported. The crystal structure of the o-arsanilic acid belongs to the monoclinic crystal system and to the P21 noncentrosymmetric space group with Z equals two.  相似文献   

13.
The title compound crystallizes in the monoclinic space group P2 1 /c with four formula units in a unit cell of dimensions a = 10.814(2), b = 8.400(2), c = 11.398(4) A, β = 110.86(2)°, V = 967.5(5) A3. The crystal structure is characterized by almost exactly planar [Me2NC(NH2)Me]+cations and [O2CNMe2 ]- anions which are approximately perpendicular oriented to one another. The amidine N1—C and N2—C bond lengths are significantly different (1.341(7) and 1.292(7) A, respectively) but the C—O distances of the carbamate anion are equal within experimental error (1.263(6) and 1.256(6) A). An essential feature of the crystal structure are N—H —O hydrogen bonds between cations and anions.  相似文献   

14.
Abstract  The synthesis and crystal structures of 1,3-diamino-2-methylimidazolium bis(trifluoromethylsulfonyl)imide (1), 1,3-dihydroxy-2-methylimidazolium bis(trifluoromethylsulfonyl)imide (2) and 1-(2-(diethylammonio)ethyl)-3-methylimidazolium bis(bis(trifluoromethylsulfonyl)imide) (4) are reported. The salts 1, 2 and 4 have melting points below 100 °C, the intermediate 1-(2-(diethylamino)ethyl)-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (3) is liquid at room temperature. Compound 1 is monoclinic, space group P21/n with a = 8.4979(4) ?, b = 12.2803(6) ?, c = 13.9400(7) ?, β = 93.086(4)°, and Z = 4. Compound 2 is monoclinic, space group P21/c with a = 7.6165(2) ?, b = 20.5323(8) ?, c = 9.7654(3) ?, β = 111.046(2)°, and Z = 4. Compound 4 is triclinic, space group with a = 8.5313(4) ?, b = 9.2157(4) ?, c = 20.5812(8) ?, α = 84.668(2)°, β = 83.738(2)°, γ = 63.096(2)°, and Z = 2. The ions in 1 build a network of N–H···O hydrogen bonds, in 2 they are linked to chains by O–H···N and bifurcated O–H···O hydrogen bonds, whereas in 4 they form pairs by N–H···O contacts. The triflimide anions adopt transoid conformations. Index Abstract  Short interionic contacts, conformational flexibility, and disorder phenomena were identified in the crystal structures of three new, low-melting, protic imidazolium triflimides.   相似文献   

15.
The metal complex, bis [2-(3-(2-((2-hydroxybenzylidene)amino)ethyl) oxazolidin-2-yl)phenol]cerium(IV) 1,4-dioxane monosolvate was synthesized and characterized by infrared, 1H NMR, elemental analysis, single-crystal, and powder X-ray diffraction. The coordination polyhedra of cerium shows a distorted square-antiprismatic geometry. No classical hydrogen bonds were observed. The crystal packing was influenced by weak C-H···O (intermolecular) and van der Waals interactions.  相似文献   

16.
Abstract Two apigenin alkylation derivatives, 4′,7-dimethoxyl-5-hydroxyflavone (I) and 4′,7-diethoxyl-5-hydroxyflavone (II), have been synthesized and their crystal structures were determined by 1H NMR and single crystal X-ray diffraction study. (I) is triclinic, space group P−1 with a = 7.120(5) ?, b = 7.297(5) ?, c = 13.559(10) ?, α = 89.313(12)°, β = 86.298(12)°, γ = 83.999(13)° and Z = 2. (II) is monoclinic, space group P 21 /c with a = 16. 309(4) ?, b = 7.303(2) ?, c = 15.185(4) ?, α = 90.00°, β = 115.70(2)°, γ = 90.00° and Z = 4. They have the same flavone skeleton which is composed of a benzopyranone moiety and a phenyl moiety. Molecules of (I) are linked into a two-dimensional network by a combination of C–H···O hydrogen bond and π–π stacking interactions. (II) shows some discrepancies with (I) and the molecules are linked into a column by π–π stacking interaction. Graphical Abstract Two apigenin alkylation derivatives, 4′,7-dimethoxyl-5-hydroxyflavone (I) and 4′,7-diethoxyl-5-hydroxyflavone (II) were synthesized and their crystal structures were determined by single-crystal X-ray diffraction. Hydrogen bonding and π–π stacking interactions assemble (I) into a two-dimensional network, and in the crystal structure of (II), π–π stacking interaction leads to the formation of a column.   相似文献   

17.
张友禄  魏莉 《人工晶体学报》2016,45(12):2878-2881
研究了对全取代环戊基六元瓜环(CyP6Q6)与结构诱导剂ZnCl2在稀盐酸条件下长的晶体进行X-射线单晶衍射分析.通过实验得到一个新的晶体,其结构表明,晶体属于斜方晶系,空间群为P21/n,a=27.599(7)(A),6=17.393(7)(A),c=18.265(5)(A),α=90.00°,β=93.369(6)°,γ=90.00°,Z=4,R=0.046,其中结构中出现了蜂巢效应并且形成了较大的孔道.  相似文献   

18.
Abstract  The two 1-aryl-5-methyl-1,2,3-triazole derivatives were prepared by the 1-aryl-5-methyl-1,2,3-triazol-4-carboxylic acids 3. The yielded products 4a–b were confirmed by NMR, MS, IR spectra. We investigated the crystalline structure of compounds 4a and 4b. Compound 4a, C9H8BrN3, Mr = 238.09, crystallizes in the monoclinic space group P2(1)/n with unit cell parameters a = 11.660(2), b = 7.668(2), c = 11.818(2) ?, α = 90.00, β = 116.01(3), γ = 90.00o. V = 949.6(3) ?3, Z = 4, Dx = 1.665 Mg m−3. The final R was 0.0477. Compound 4b, C13H11N3, Mr = 209.25, crystallized in the orthorhombic space group Pbca with unit cell parameters a = 10.373(2) ?, b = 11.691(2) ?, c = 17.579(4) ?, α = 90.00o, β = 90.00o, γ = 90.00o, V = 2131.8(7) ?3, Z = 8, D m = 1.304 Mg m−3. The final R was 0.0565. Index Abstract  The two 1-aryl-5-methyl-1,2,3-triazole derivatives were prepared by the 1-aryl-5-methyl-1,2,3-triazol-4-carboxylic acids 3. The yielded products 4ab were confirmed by NMR, MS, IR spectra. We investigated the crystalline structure of compounds 4a and 4b. Compound 4a, C9H8BrN3, Mr = 238.09, crystallizes in the monoclinic space group P2(1)/n with unit cell parameters a = 11.660(2), b = 7.668(2), c = 11.818(2)  ?, α = 90.00, β = 116.01(3), γ =90.00o. V = 949.6(3) ?3, Z = 4, Dx = 1.665 Mg m−3. The final R was 0.0477. Compound 4b, C13H11N3, Mr = 209.25, crystallized in the orthorhombic space group Pbca with unit cell parameters a = 10.373(2) ?, b = 11.691(2) ?, c = 17.579(4) ?, α = 90.00o, β = 90.00o, γ = 90.00o, V = 2131.8(7) ?3, Z = 8, D m = 1.304 Mg m−3. The final R was 0.0565.   相似文献   

19.
The crystal and molecular structure of the antimalarial compound 5,7-methoxy-8-(3-methyl-1-buten-3-ol)-coumarin, C16H18O5, M r = 290.3 Da, has been determined from X-ray diffraction data. The material crystallizes in the monoclinic space group P21/c with 4 molecules per unit cell of dimensions a = 8.9044(9), b = 17.623(1), c = 10.175(1) Å, = 113.97(1)°, crystal density D c = 1.322 g/cm3. The structure was determined using direct methods and refined by full-matrix least squares to a conventional R index of 0.066 for 2416 measured reflections and 206 parameters.The coumarin ring system is almost planar with the methoxy C atoms rotated slightly out of the coumarin mean plane. Apart from the terminal CH3 groups C(12) and C(13), which are 1.184(3) Å above and –1.315(3) Å below the plane, the 3-methyl-1-buten-3-ol substituent is planar (rms deviation 0.009 Å) making an angle of 6.31(7)° with the phenyl ring. One intermolecular hydrogen bond is present in the crystal structure between O(5)–HO(5) and the symmetry related O(2) oxygen, generated by the symmetry operation (x, 1/2 – y, –1/2 + z).  相似文献   

20.
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