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1.
Crystal structures are reported for four organoantimony(III) halides, i.e. ( p-tolyl)antimony dichloride (1) and dibromide (2), diphenylantimony bromide (3), (biphenyl-2,2′-diyl) antimony chloride (4) and a new antimony(V) compound, bis(2′-chlorobiphenyl-2-yl)antimony(V) trichloride (5), obtained by oxidising (4) with an excess of chlorine. The two tolyl compounds (1) and (2), which are isostructural and also isostructural with the corresponding phenyl derivatives, contain pyramidal CSbX 2 units. These are interlinked by (a) two weak intermolecular Sb halogen interactions (mean 3.54 and 3.69 Å for the chloride and bromide, respectively), raising the antimony coordination number to five giving infinite chains, and (b) weak contacts between antimony and three of the carbon atoms of a symmetry-related tolyl group (mean 3.41 and 3.42 Å for the chloride and bromide, respectively). There are no intermolecular Sb Br contacts in 3 but two Sb C interactions (mean 3.64 Å) interconnect the pyramidal monomers. Such Sb C interactions (mean 3.43 Å) are also present in the biphenylyl derivative 4, in which the C---Sb---C angle in the pyramidal monomer is constrained to 81.0° by the short bite of the biphenylyl group. Loose dimers are formed in the solid state by Sb Cl contacts at 3.71 Å. In contrast to the chlorine bridged dimeric structure of Ph2SbCI3, compound 5 is a distorted trigonal bipyramidal monomer in the solid state, providing the first example of an antimony(V) compound with chlorine atoms in both axial and equatorial sites. As expected, distances to the two axial chlorines are substantially longer (2.420(3), 2.421(3) Å) than that to the equatorial atom (2.280(3) Å). The greatest distortion is shown by the equatorial C---Sb---C angle, which is increased to 137.1°, probably as a consequence of the steric requirements of the bulky chlorobiphenylyl groups. 相似文献
2.
N-2-(4-picolyl)- N′-2-chlorophenylthiourea, 4PicTu2Cl, monoclinic, P2 1/ c, a=10.068(5), b=11.715(2),
β=96.88(4)°,
and Z=4; N-2-(6-picolyl)- N′-2-chlorophenylthiourea, 6PicTu2Cl, triclinic, P-1, a=7.4250(8), b=7.5690(16), c=12.664(3) Å, =105.706(17), β=103.181(13), γ=90.063(13)°, V=665.6(2) Å 3 and Z=2 and N-2-(6-picolyl)- N′-2-bromophenylthiourea, 6PicTu2Br, triclinic, P-1, a=7.512(4), b=7.535(6), c=12.575(4) Å, a=103.14(3), β=105.67(3), γ=90.28(4)°, V=665.7(2) Å 3 and Z=2. The intramolecular hydrogen bonding between N′H and the pyridine nitrogen and intermolecular hydrogen bonding involving the thione sulfur and the NH hydrogen, as well as the planarity of the molecules, are affected by the position of the methyl substituent on the pyridine ring. The enthalpies of fusion and melting points of these thioureas are also affected. 1H NMR studies in CDCl 3 show the NH′ hydrogen resonance considerably downfield from other resonances in their spectra. 相似文献
3.
Structures of the following compounds have been obtained: N-(2-pyridyl)- N′-2-thiomethoxyphenylthiourea, PyTu2SMe, monoclinic, P2 1/ c, a=11.905(3), b=4.7660(8), c=23,532(6) Å, β=95.993(8)°, V=1327.9(5) Å 3 and Z=4; N-2-(3-picolyl)- N′-2-thiomethoxyphenyl-thiourea, 3PicTu2SeMe, monoclinic, C2/ c, a=22.870(5), b=7.564(1), c=16.941(4) Å, β=98.300(6)°, V=2899.9(9) Å 3 and Z=8; N-2-(4-picolyl)- N′-2-thiomethoxyphenylthiourea, 4PicTu2SMe, monoclinic P2 1/ a, a=9.44(5), b=18.18(7), c=8.376(12) Å, β=91.62(5)°, V=1437(1) Å 3 and Z=4; N-2-(5-picolyl)- N′-2-thiomethoxyphenylthiourea, 5PicTu2SMe, monoclinic, C2/ c, a=21.807(2), b=7.5940(9), c=17.500(2) Å, β=93.267(6)°, V=2893.3(5) Å 3 and Z=8; N-2-(6-picolyl)- N′-2-thiomethoxyphenylthiourea, 6PicTu2SMe, monoclinic, P2 1/ c, a=8.499(4), b=7.819(2), c=22.291(8) Å, β=90.73(3)°, V=1481.2(9) Å 3 and Z=4 and N-2-(4,6-lutidyl)- N′-2-thiomethoxyphenyl-thiourea, 4,6LutTu2SMe, monoclinic, P2 1/ c, a=11.621(1), b=9.324(1), c=14.604(1) Å, β=96.378(4)°, V=1572.4(2) Å 3 and Z=4. Comparisons with other N-2-pyridyl- N′-arylthioureas having substituents in the 2-position of the aryl ring are included. 相似文献
4.
The structures of 3,3′-dicarbometoxy-2,2′-bipyridine ( dcmbpy) complexes with copper(II) and silver(I) cations have been determined using single crystal X-ray-diffraction. The crystals of Cu( dcmbpy)Cl 2 are monoclinic, C2/ c, a = 16.966(3), b = 18.373(3), c = 13.154(2) Å, β = 126.543(3)°. The crystals of Ag( dcmbpy)NO 3 · H 2O are also monoclinic, C2/ c, a = 16.7547(13), b = 11.0922(9), c = 18.7789(18) Å, β = 100.228(7)°. The results have been compared with the literature data on the complexes of dcmbpy and its precursors: 2,2′-bipyridine ( bpy) and 3,3′-dicarboxy-2,2′-bipyridine ( dcbpy). Two types of complexes of 3,3′-carboxy derivatives of bpy are distinguished: (1) with metal atom bonded to two N atoms of the same molecule and (2) with metal atom bonded to two N atoms of two different molecules. The Cu( dcmbpy)Cl 2 complex belongs to the first type, whereas Ag( dcmbpy)NO 3 · H 2O belongs to the second type. 相似文献
5.
Two novel Cu(II) complexes with 1,2-bis(2′-methyl-5′-(2″-pyridyl)-3′-thienyl)perfluorocyclopentene (BM-2-PTP) or its closed-form (closed-BM-2-PTP) were synthesized and characterized by X-ray crystallographic analysis. Both complexes are tetra-coordinated to two N atoms from distinct ligands and two Cl atoms from anions, forming 1-D polymeric structures. [Cu(BM-2-PTP)Cl 2] (1) showed typical spectral changes as analogous Ag(I) complexes with the same ligand upon appropriate light stimulus. However, closed-BM-2-PTP displayed different photocyclization from its open-ring form upon irradiation with UV light, indicating the photogenerated closed form turned into two kinds of closed-ring isomers. Furthermore, [Cu(closed-BM-2-PTP)Cl 2] (2) was revealed to contain two conformers by X-ray crystallographic analysis and displayed similarities in photocyclization to its free ligand. The distinct absorptions of the UV spectrum were attributed to the coexistence of two conformers in complex 2, both of which showed effective photoreactivities in the crystalline phase. The photochromic mechanism of complex 2 is tentatively concluded as two conformers displaying independent photoreactions. 相似文献
6.
Triphenyltelluronium hexachloroplatinate (1), hexachloroiridate (2), tetrachloroaurate (3), and tetrachloroplatinate (4) were prepared from Ph 3TeCl and potassium salts of the corresponding anions. Upon recrystallization of 4 from concentrated nitric acid, K 2[PtCl 6] and (Ph 3Te)(NO 3)·HNO 3 (5) were obtained. The crystal structures of 1–3 and 5 are reported. Compounds 1 and 2 are isostructural. They are triclinic, P
, Z=2 (the asymmetric unit contains two formula units). Compound 1: a=10.7535(2), b=17.2060(1), c=21.4700(3) Å, =78.9731(7), β=77.8650(4), γ=78.8369(4)°. Compound 2: a=10.7484(2), b=17.1955(2), c=21.4744(2) Å, =78.834(1), β=77.649(1), γ=78.781(1)°. Compound 3 is monoclinic, P2 1/ c, Z=4, a=8.432(2), b=14.037(3), c=17.306(3) Å, β=93.70(3)°. Compound 5 is monoclinic. P2 1/ n, Z=4, a=9.572(2), b=14.050(3), c=13.556(3) Å, β=90.76(3)°. The primary bonding in the Ph 3Te + cation in each salt is a trigonal AX 3E pyramid with Te---C bond lengths in the range 2.095(8)–2.14(2) Å and the bond angles 94.1(6)–100.9(5)°. The weak TeCl (1–3) and TeO (5) secondary interactions expand the coordination sphere. In 1 and 2 the cation shows a trigonal bipyramidal AX 3YE coordination with one primary Te---C bond and the shortest secondary TeCl contact in axial positions and the two other Te---C bonds and the lone-pair in equatorial positions. The cation in 3 shows a distorted octahedral AX 3Y 3E environment and that in 5 is a more complex AX 3Y 3Y′ 2 arrangement. In both latter salts the structure is a complicated three-dimensional network of cations and anions. 相似文献
7.
The photophysics of three complexes of the form Ru(bpy) 3−(pypm) 2+ (where bpy2,2′-bipyridine, pypm 2-(2′-pyridyl)pyrimidine and P=1, 2 or 3) was examined in H 2O, propylene carbonate, CH 3CN and 4:1 (v/v) C 2H 5OH---CH 3OH; comparison was made with the well-known photophysical behavior of Ru(bpy) 32+. The lifetimes of the luminescent metal-to-ligand charge transfer (MLCT) excited states were determined as a function of temperature (between −103 and 90 °C, depending on the solvent), from which were extracted the rate constants for radiative and non-radiative decay and Δ E, the energy gap between the MLCT and metal-centered (MC) excited states. The results indicate that *Ru(bpy) 2(pypm) 2+ decays via a higher lying MLCT state, whereas *Ru(pypm) 32+ and *Ru(pypm) 2(bpy) 2+ decay predominantly via the MC state. 相似文献
8.
Two new Cd(II) complexes with a 3-(2-pyridyl)pyrazole-based ligand, [Cd(L) 2(SCN) 2] (1) and {[Cd(L) 2N 3](ClO 4)} n (2) (L=3-(2-pyridyl)pyrazol-1-ylmethylbenzene) were synthesized and structurally characterized by elemental analyses, IR and single crystal X-ray diffraction analysis. Complex 1 crystallizes in the monoclinic system, space group C2/ c, with a=14.833(3), b=13.790(3), c=15.970(3) Å, β=110.89(3)° and Z=4, while 2 crystallizes in the monoclinic system, space group P2 1/ c, with a=13.622(4), b=23.286(7), c=10.547(3) Å, β=111.084(6)° and Z=4. In the two complexes, the Cd(II) centers are coordinated by six nitrogen atoms, in which four from two distinct L ligands and two from thiocyanato (1) or azido (2) anions. Complex 1 has a mononuclear structure, whereas 2 has a 1D chain structure bridged by azido anions. In 2, the azido adopts a μ-1,3- trans coordination mode, which is not common in the azide Cd(II) complexes. In addition, in the structure of 2, the 1D chains were further assembled into a quasi-3D supramolecular network by the C–HO hydrogen-bonding interactions. The structural difference of the two complexes is attributable to the different anions, which have different coordination natures. 相似文献
9.
Toluene solutions of M 2(NMe 2) 6 (M = Mo, W) react with mesitylene selenol (Ar′SeH) to give M 2(SeAr′) 6 complexes. MO 2(OR) 6 (R = tBu, CH 2tBu) react with excess> 6 fold) Ar′SeH to give Mo 2 (SeAr′) 6, whilst W 2(OR) 6(py) 2 (R = iPr, CH 2tBu) react with excess (> 6 fold) Ar′SeH to give W 2(OR) 2(SeAr′) 4. Reaction of MO 2(OPr i) 6 with Ar′SeH produces Mo 2(OPr i) 2 (SeAr′) 4 which crystallizes in two different space groups. These areneselenato complexes are air-stable and insoluble in common organic solvents. X-ray crystallographic studies revealed that the Mo 2(SeAr′) 6 and W 2(SeAr′) 6 compounds are isostructural in the solid state and adopt ethane-like staggered configurations with the following important structural parameters, M---M (W---W/Mo---Mo) 2.3000(11)/2.2175(13) Å, M---Se 2.430 (av.)/2.440 (av.) Å, M---M---SE 97.0° (av.)°. In the solid state W 2(O iPr) 2(SeAr′) 4 adopts the anti-configuration with crystallographically imposed Ci symmetry and W---W 2.3077(7) Å, W---Se 2.435 (av.) Å, W---O 1.858(6) Å; W---W---SE 100.27(3)°, 93.8(3)° and W---W---O 108.41(17)°. Mo 2(OPr i) 2(SeAr′) 4 crystallizes in both P
and A2/ a space groups in which the molecules are isostructural with each other and the tungsten analogue. Important bond lengths and angles are Mo---Mo 2.180(24) Å, Mo---Se 2.432(av.) Å, Mo---O 1.872(9) Å, Mo---Mo---Se 99.39(9)°, 94.71(8)°, Mo---Mo---O 107.55(28)°. 相似文献
10.
Two new coordination polymers of copper(I) chloride and pyrazinic acid (pyz-H), namely [CuCl(pyz-H) 2]·2H 2O (1) and [Cu 2Cl 2(pyz)(H 2O)]·H 2O (2) have been prepared and characterized by spectroscopic, magnetic and crystallographic methods. The overall physical measurements suggest that 1 is diamagnetic and contains monodentate N-pyrazinic acid, whereas 2 is paramagnetic and contains tridentate N, N′, O- chelating bridging pyrazinato anion. In the structure of 1 as elucidated by X-ray single crystal analysis, the asymmetric units [CuCl(pyz) 2] are linked together forming a zigzag chain with tetrahedral copper(I) environment. The two lattice water molecules form hydrogen bonds with the uncoordinated N atom and carboxylate group O atom of pyz-H molecules. The Cu–N bond lengths are 2.009(6) Å and Cu–Cl distances are 2.337(2) Å. Complex 2 has a three-dimensional structure with the chains [Cu(I)Cu(II)(C 5H 3N 2O 2)Cl 2(H 2O)] interconnected by [Cu(I)Cl 2N] tetrahedral unit and [Cu(II)NO 2Cl 2] polyhedra. The Cu(I)–Cl and Cu(I)–N distances are 2.327(2)–2.581(2) Å and 1.988(6) Å, respectively, whereas the Cu(II)–Cl and Cu(II)–N bond lengths are 2.258(2), 2.581(2) Å, and 2.017(6) Å, respectively. Hydrogen bonds of the type O–HO are formed between lattice and coordinated water, and carboxylate oxygens of pyrazinato ligand giving rise to a three-dimensional network. The Cl − anions act as bridging ligands in both complexes. The magnetic data of complex 2 have been measured from 2 to 300 K and discussed. 相似文献
11.
The room temperature photophysical properties of several sulphonated and unsulphonated 6-(2′-hydroxy-4′-methoxyphenyl)- s-triazines were investigated in a range of solvents by means of steady state and picosecond fluorescence spectroscopy. Compounds possessing phenyl or p-tolyl groups in the s-triazinyl ring exhibit only a very weak normal Stokes-shifted fluorescence, arising from the initially excited chromophore. Substitution of phenoxy groups into the s-triazinyl ring results in the appearance of an additional longer-wavelength fluorescence which is assigned to the keto tautomer, formed following excited state intramolecular proton transfer (ESIPT). The rate constant for the (ESIPT) process that occurs in sodium 3-(3′,5′-diphenoxy-2′,4′,6′-triazinyl)-4-hydroxy-2-methoxybenzene sulphonate in water is estimated to be greater than 10 11 s −1. 相似文献
12.
The complex Fe(η 6-C 5H 5CMe 3) 2 crystallizes in the centrosymmetric triclinic space group P
( Ci1; No. 2) with unit cell dimensions of a 8.770(1) Å, b 8.878(1) Å, c 11.991(1) Å, 107.56(1)°, β 90.85(1)°, γ 90.13(1)°, V 890.0(2) Å 3 and Z = 2. A full sphere of data was collected on a four-circle diffractometer. The structure was solved and refined to R 7.93% for all 3155 independent reflections and R 4.98% for those 2002 data with | F0 | > 6σ. | F0 |. The molecules lie on crystallographic inversion centers at 0, 0, 0 and 1/2, 0, 1/2; the crystallographic asymmetric unit therefore consists of two independent half molecules. The molecule centered at 0, 0, 0 (molecule “A”) is ordered and well-defined; that centered on 1/2, 0, 1/2 (molecule “B”)is probably disordered, as indicated by larger “thermal parameters” and a greater range of apparent interatomic distances. Discussion em phasizes the geometry of molecule A, which has precise Ci symmetry with Fe(1A)-B(1A) 2.297(4) Å and Fe(1A)-C(ring) distances ranging from 2.057(6) Å to 2.138(4) Å. 相似文献
13.
Oxindole reacts with p-nitrobenzyl chloride ot give 3-(4′-nitrobenzyl) oxindole, but with o-nitrobenzyl chloride abnormal product, 2′-hydroxy-spiro[2H-indole-2,3′-3′H-indole] (Vb) is produced. The structure of Vb has been elucidated on the basis of the IR, UV and mass spectra, and confirmed by the analogous reactions of 3-methyl-, 4-methyl- and 3,3-dimethyloxindoles with o-nitrobenzyl chloride. Isatin reacts with o-nitrobenzyl chloride to give o-nitrobenzyloxireno[,3]-oxindole (X). 相似文献
14.
The crystal structure of NdCl 3·C 6H 12O 6·9H 2O has been determined. It crystallizes in the monoclinic system, p2(1)/ n space group with cell dimensions: a=15.824(3) Å, b=8.633(2) Å, c=16.219(3) Å, β=107.24°, V=2116.1(7) Å 3 and Z=4. Each Nd ion is coordinated to nine oxygen atoms, two from inositol and seven from water molecules, with an Nd–O distance of 2.449–2.683 Å, the other two water molecules are hydrogen bonded. No direct contacts exist between Nd and Cl. There is an extensive network of hydrogen bonds in hydroxyl groups, water molecules and chloride ions in the crystal structure of the lanthanide complex. The Raman spectra of Pr–, Nd– and Sm–inositol are similar, which show that the three metal ions have the same coordination mode. The Raman spectra are consistent with their structures. 相似文献
15.
The crystal and molecular structure of the N-(4-chloro)benzoyl- N′-(4-tolyl)thiourea (C 15H 13N 2OSCl, Mr=304.79) is determined by X-ray diffraction. The crystal structure is monoclinic, space group: P2 1/ n, a=16.097(6), b=4.5989(2), c=19.388(7) Å and β=89.299(6)° V=1434.7(9)Å 3, Z=4. FTIR and NMR spectra have been characterized. The interactions of intramolecular and intermolecular hydrogen bonds have been discussed. Density functional theory (DFT) (B3LYP) methods have been used to determine the structure and energies of stable conformers. Minimum energy conformations are calculated as a function of the torsion angle θ (C13–N1–C14–N2) varied every 30°. The optimized geometry corresponding to crystal structure is the most stable conformation. This has partly been attributed to intramolecular hydrogen bonds. With the basis sets of the 6-311G* quality, the DFT calculated bond parameters and harmonic vibrations are predicted in a very good agreement with experimental data. 相似文献
16.
The enzymatic kinetic resolution of the racemic alcohols 1-(3′-furyl)-3-buten-1-ol (±)-1 and 2-(2′-furyl)propan-1-ol (±)-2 was investigated by screening a range of lipases and esterases for enantioselective transacylation, as well as for enantioselective hydrolysis. For both alcohols, lipase-catalyzed hydrolysis of the derived racemic acetate gave the best results for accessing the desired ( S)-enantiomers. In the case of the secondary alcohol (±)-1, ASL turned out to be the optimum enzyme, whereas PPL was found to be superior in the case of the primary alcohol (±)-2. Additionally, an alternative access to ( S)-2 via Oppolzer's camphor sultam methodology is described. 相似文献
17.
Molecules of C 12H 4F 8N 2 crystallize in the orthorhombic space group P2 12 12 1 with cell constants a=9.200(1), b=10.896(1), c=23.178(3) Å and V=2323.4(5) Å 3. There are two molecules in the asymmetric unit which have D 2 symmetry. However these two molecules have C 2 symmetry in central C–C bonds, separately. Intramolecular steric repulsions between F atoms and N–HF hydrogen bonds have very much affected the molecular conformation. The mean dihedral angle between intramolecular phenyl rings is 119.2(1)°. The N–C bonds have lengths 1.363(4)–1.407(4) Å with a mean of 1.388 Å. This is shorter than the conventional C–N (1.47(1) Å) bond length due to π-electron delocalizations (F.H. Allen, O. Kennard, D.G. Watson, L. Brammer, A.G. Orpen, R. Taylor, J. Chem. Soc. Perkin Trans. II (1987) S1–S19). The molecular structure of the title compound was also investigated by IR spectroscopy. It was shown that the IR spectra are in agreement with the crystal structure. On the other hand, theoretical and semi-emprical molecular mechanic calculations were carried out to obtain the most probable low-energy conformations by using MM3, PM3 and AM1 programs. 相似文献
18.
The crystal structure of N,N′-bis(β-chloroethyl)-glutaramide (NNCEG) has been determined by X-ray diffraction analysis, as part of a research programme on simple model compounds for synthetic polyamides. It crystallizes in the monoclinic system, space group P2 1 Z = 2, with A = 4·941, B = 28·123, C = 4·835 Å and β = 113°53′. The structure was solved by the heavy atom method and refined to a final R value of 0·079. Each molecule forms hydrogen bonds along two directions (almost the a and the c directions with an angle close to 60°) giving rise to bidimensional layers (parallel to the ac plane with width b/2). A similar system of hydrogen bonds could be postulated for some nylons with odd number of CH 2's between amide groups. The molecular conformation different from an all trans conformation is discussed in terms of the barriers to rotation around each bond considered by several authors. The twinning observed in most of the examined crystals is rationalized in terms of simple symmetry operations on molecular conformations of opposite chirality. 相似文献
19.
Lithium 2-thienyltellurolate, generated from 2-thienyl lithium, reacts at −78 °C in THF with chloroethyl ethyl sulfide to give a (Te, S) ligand 1-ethylthio-2-[2-thienyltelluro]ethane (L) as a red oil. The complexes [PdCl 2(L)] (1), [PtCl 2(L)] (2), [Ag(L) 2][ClO 4] (3) and [CuBr(L)] 2 (4) were synthesized. The complex [HgCl 2(L)] on crystallization decomposed giving Th 2TeCl 2 (5) [where Th = 2-thienyl], which was characterized by X-ray diffraction on its single crystals. The ligand L and complexes 1–4 exhibit proton and carbon-13 NMR spectra, which are characteristic. The coordination through Te in 1–4 is indicated by downfield coordination shifts in the position of the TeCH 2 signal of L. Complex 1 was characterized by X-ray diffraction on its single crystals. The geometry around Pd is square planar. The Pd–Te, Pd–S and Pd–Cl bond lengths are 2.5040(4), 2.273(1) and 2.322(1)/2.380(1) Å, respectively. There are intermolecular interactions between Te (coordinated to Pd) and Cl, and sulfur and Cl. The Te–Cl and S–Cl distances, 3.401 and 3.488 Å, respectively, are shorter than the sum of the van der Waal’s radii (3.81 and 3.55 Å, respectively). The Pd–Pd distance between the two molecules is 3.4156(6) Å, greater than the sum of van der Waal’s radii (3.26 Å). The structure of 5 is typical of that of a tellurium(IV) compound (saw-horse type). The two Te–Cl bond lengths are identical, 2.480(1) Å. The geometry around Te in 5 can be best described as pseudo tetrahedral (trigonal bipyramidal with a lone pair on one corner of the triangle). 相似文献
20.
The title compound, 5-N-i-propyl-2-(2′-nitrobenzenesulfonyl)-glutamine, was synthesized and its structure was confirmed by IR, MS, 1H NMR, and elemental analysis. The single crystal structure of the title compound was determined by X-ray diffraction. The crystal belongs to Monoclinic, space group P2 (1), with a = 0.69281(11) nm, b = 0.76508(12), c = 1.5843(3) nm, = 90°, β = 90.941(3)°, γ = 90°, V = 0.8397(2) nm 3, Z = 2, Dc = 1.477 g/cm 3, μ = 0.236 mm -1, F(000) = 392, R = 0.0297, and wR = 0.0664. 相似文献
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