首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 218 毫秒
1.
Crystal and Molecular Structure of Bis[N-(diethylaminothiocarbonyl)-N′-phenyl-benz-amidinato]nickel(II) The structure of bis[N-(diethylaminothiocarbonyl)-N′-phenyl-benzamidinato]-nickel(II) has been determined by X-ray structure analysis. The compound crystallizes in orthorhombic space group P212121 with a = 16.36, b = 16.94, c = 12.96 Å and Z = 4. The solution of the structure was performed by heavy atom technique and gave a final R value of R = 0.055 for 1764 observed reflections. The coordination polyhedron has a tetrahedrally distorted shape. The ligator atoms are arranged in cis position. The chelate rings deviate clearly from planarity. Against the chelate rings the phenyl rings are appreciably twisted. The title compound is compared regarding its structure with the analogous copper chelate.  相似文献   

2.
Crystal and Molecular Structure of N,N′-o-Phenylen-bis-(N″,N″-diethyl-N?-benzimidoyl-thioureato)nickel(II) The structure of the title compound has been determined by an X-ray structure analysis. The compound crystallizes in the monoclinic space group C2/c with a = 38.896, b = 14.326, c = 11.121 Å, β = 102.33° and Z = 8. The solution of the structure was performed by Patterson methods. The final R value was R = 0.053 for 2260 observed reflections. The coordination geometry is nearly planar. The ligator atoms show as a necessity a cis arrangement. The chelate rings deviate from planarity. The phenyl rings and the phenylene fragment are significantly twisted in respect to the chelate rings.  相似文献   

3.
Crystal and Molecular Structure of Bis[N-(diethylaminothiocarbonyl)-benzamidine]-silver(I) Nitrate The crystal structure of bis[N-(diethylaminothiocarbonyl)-benzamidine]silver(I) nitrate has been determined by X-ray structure analysis on a single crystal. The compound is monoclinic, space group P21/n with a = 12.541, b = 43.470, c = 11.096 Å, β = 106.27° and 8 formula units per unit cell. The structure was solved by application of direct methods to difference structure factors (DIRDIF) and refined for 5242 observed reflections to a final R value of R = 0.070. There are two symmetrically independent molecules of the title compound in the asymmetric unit. The central Ag ion is coordinated by the S atoms of two ligands. The nitrate ions do not coordinate. The coordination geometry is slightly bent.  相似文献   

4.
Incomplete Chelation by N-Acylthioureas: Structure of Bis[N-(1-pyrrolidinyl-thiocarbonyl)-benzamidato] mercury(II) Bis[N-(1-pyrrolidinyl-thiocarbonyl)-benzamidato]mercury(II) crystallizes in the monoclinic space group P21/c with a = 10.126, b = 22.347, c = 11.384 Å, β = 109.13° and Z = 4. The structure was solved by application of direct methods to difference structure factors (DIRDIF). The final R value was R = 0.06 for 2195 observed reflections. Mercury exhibits the characteristic coordination number 2 with linear arrangement of the S ligators. Both O ligators, however, show weak bonds to Hg. For that reason the mercury complex should be better described as a labilized chelate with the effective coordination number 4. With regard to the excellent extractibility of mercury(II) with N-acylthioureas the formation and existence, respectively, of such a labilized chelate seems to be favourable.  相似文献   

5.
Synthesis, Properties, and Structure of [2-(1′-methyl-4-imidazolyl)phenyl-1-C,3′-N]-palladium(II) Acetylacetonate The reaction of Di-μ-chloro-bis[2-(1′-methyl-4-imidazolyl)phenyl-1-C,3′-N]palladium(II) with Thallium(I) acetylacetonate yields [2-(1′-methyl-4-imidazolyl)phenyl-1-C,3′-N]palladium(II) acetylacetonate. The complex crystallizes monoclinic in the space group P21/n with the lattice constants a = 1302.4(3), b = 836.0(2), c = 1341.3(3) pm, β = 93.69(3)°. Pd has a squareplanar coordination by two O atoms of acetylacetonate, the N atom of the imidazole ring, and the C atom of the phenyl group. I.r., n.m.r., and mass spectra are reported.  相似文献   

6.
Three bidentate, mixed-donor ligands based on a triphenylphosphine unit bearing a pyrazole group in the ortho-position of one phenyl ring have been synthesised; the N,P ligand [2-(3-pyrazolyl)phenyl]diphenylphosphine pzphos has been synthesised and transformed into new N,P(O) and N,P(S) derivatives, [2-(3-pyrazolyl)phenyl]diphenylphosphine oxide pzphos(O) and [2-(3-pyrazolyl)phenyl]diphenylphosphine sulfide pzphos(S), respectively. The coordination chemistry of pzphos and pzphos(O) towards palladium(II) has been investigated. Depending on the ligand to metal molar ratio employed in the reactions of palladium(II) with pzphos, either the 1 : 1 chelate [Pd(pzphos)Cl2] 1a or the 2 : 1 N,P chelate [Pd(pzphos)2]Cl2 1b was obtained. 1b contains two six-membered chelate rings in which the chlorides have been displaced from the inner coordination sphere of palladium. Exchange of the chloride anions in 1b for perchlorate anions was achieved using AgClO4 to give [Pd(pzphos)2][ClO4]2 1c. Reaction of pzphos(O) under the same conditions forms the 2 : 1 adduct [Pd(pzphos(O))2Cl2] 2b regardless of the metal to ligand ratio or the order of addition of reactants. Unlike the N,P chelate 1b, the N,P(O) ligands in complex 2b bind in a monodentate fashion through the N-donor atoms of the pyrazole rings. Abstraction of the chloro ligands in compound 2b using AgClO4 gave the 2 : 1 N,P(O) chelate [Pd{pzphos(O)}2][ClO4]2 2c, in which entropically unfavourable 7-membered chelate rings are formed. X-Ray diffraction has been used to confirm the solid-state structures of the pzphos(O) ligand and the complexes 1b, 1c, 2b and 2c.  相似文献   

7.
Russian Journal of Organic Chemistry - A series of N-(4-oxoadamantan-1-yl)-N′-[fluoro(chloro)phenyl]ureas have been synthesized in 27–73% yields by reaction of...  相似文献   

8.
D.M. Roundhill 《Polyhedron》1983,2(9):959-962
Copper(II) acetate reacts with N-(2-ethanethiol)salicylideneimine forming an ONNO chelate of α,α′-(diethylenedisulphide)-N,N′-disalicylideneimine with an uncoordinated disulphide. This copper(II) complex can also be obtained in higher yield if the thiol is first oxidized to disulphide with iodine. The geometry about copper(II) is distorted from planar to a flattened tetrahedron.  相似文献   

9.
Thioureato Brigded Binuclear Complexes of the Lanthanides Synthesis and Crystal Structure of [{PhC(NPh)NC(S)NEt2}{Et2NC(S)NH}LnBr(thf)]2 (Ln = Gd, Sm) The reaction of potassium-N-(diethylaminothiocarbonyl)-N′-phenyl-benzamidinat with LnBr3 (Ln = Gd, Sm) leads to the formation of the binuclear complexes [{PhC(NPh)NC(S)NEt2}{Et2NC(S)N}LnBr(thf)]2} (Ln = Gd 1 , Sm 2 ). The two bridging thiureatoligands are probably built during the reaction of potassium with the starting ligand. Coordination by one N-(diethylaminothiocarbonyl)-N′-phenylbenzamidinato-ligand, one Br-ion and one THF-ligand leads to square antiprismatic coordination of the lanthanoids. The structures of both compounds were characterized by X-ray analysis ( 1 : P1 (Nr.2), Z = 1, a = 12,006(4) Å, b = 12,245(4) Å, c = 13,612(3) Å, α = 70,55(3)°, β = 68,21(3)°, γ = 81,31(3)° 2 : P1 (Nr.2), Z = 1, a = 11,803(3) Å, b = 12,344(5) Å, c = 12,797(8) Å, α = 103,07(5)°, β = 101,76(3)°, γ = 114,13(3)°)  相似文献   

10.
Treatment of complex trans-[RuCl(2)(eta(2)-C(2)H(4))[kappa(3)-N,N,N-(R,R)-Ph-pybox]] [(R,R)-Ph-pybox = 2,6-bis[4'-(R)-phenyloxazolin-2'-yl]pyridine] with phosphines or phosphites in dichloromethane at 50 degrees C leads to the formation of novel ruthenium(II)-pybox complexes trans-[RuCl(2)(L)[kappa(3)-N,N,N-(R,R)-Ph-pybox]] [L = PPh(3) (1 a), PPh(2)Me (2 a), PPh(2)(C(3)H(5)) (3 a), PPh(2)(C(4)H(7)) (4 a), PMe(3) (5 a), PiPr(3) (6 a), P(OMe)(3) (7 a) and P(OPh)(3) (8 a)]. Likewise, reaction of trans-[RuCl(2)(eta(2)-C(2)H(4))[kappa(3)-N,N,N-(R,R)-Ph-pybox]] with PPh(3) or PiPr(3) in refluxing methanol leads to the complexes cis-[RuCl(2)(L)(kappa(3)-N,N,N-(R,R)-Ph-pybox] [L = PPh(3) (1 b), PiPr(3) (6 b)]. No trans-cis isomerisation of complexes 1 a-8 a has been observed. Complexes 1 a-8 a, 1 b, 6 b together with the analogous trans-[RuCl(2)[P(OMe)(3)][kappa(3)-N,N,N-(S,S)-iPr-pybox]] (10 a) and the previously reported trans- and cis-[RuCl(2)(PPh(3))[kappa(3)-N,N,N-(S,S)-iPr-pybox]] (9 a and 9 b, respectively) are active catalysts for the transfer hydrogenation of acetophenone in 2-propanol in the presence of NaOH (ketone/cat/NaOH 500:1:6). cis-Ph-pybox derivatives are the most active catalysts. In particular, cis complexes 1 b and 6 b led to almost quantitative conversions in less than 5 min with a high enantioselectivity (up to 95 %). A variety of aromatic ketones have also been reduced to the corresponding secondary alcohols with very high TOF and ee up to 94 %. The overall catalytic performance seems to be a subtle combination of the steric and/or electronic properties both the phosphines and the ketones. A high TOF (27 300 h(-1)) and excellent ee (94 %) have been found for the reduction of 3-bromoacetophenone with catalyst 6 b. Reductions of alkyl ketones also proceed with high and rapid conversions but low enantioselectivities are achieved.  相似文献   

11.
Crystal and Molecular Structure of Bis(1,1-diethyl-3-benzoyl-thioureato)copper(II) Bis(1,1-diethyl-3-benzoyl-thioureato)copper(II) exists in three monoclinic modifications, of which the crystallographic data have been determined. The crystal and molecular structure of one of the three modifications has been determined by X-ray structure analysis. This modification crystallizes in the space group P21/c with a = 8.871, b = 29.492, c = 12.281 Å, β = 124.50° and with 4 formula units per unit cell. The structure was solved by heavy atom technique and refined to a final R value of R = 0.05. The coordination polyhedron is a distorted tetrahedron. The S and O atoms are arranged in cis position. The chelate rings are not planar but distorted in characteristic manner.  相似文献   

12.
121Sb Mössbauer Spectra. IV. Benzamidine Complexes of Antimony(V). Crystal Structure of [Ph2Cl2Sb(N2Me2CPh)] The 121Sb Mössbauer spectra of the octahedral benzamidine complexes [Cl4Sb[BAN)]] ( I ), [Ph2Cl3Sb(BAN)] ( II ), [Ph2Cl2Sb(BAN)] ( III ), and [Ph3ClSb(BAN)] ( IV ) (BAN = N,N′-dimethyl-benzamidine) were measured at 4.2 K. The configuration of the complexes II–IV is derived from the values of the quadrupol split. In II the phenyl group is arranged in the axis, III contains both phenyl groups in equatorial position, located in trans-position to the N atoms of the chelate ligand, whereas in IV one phenyl group is placed axially, the other two are in equatorial position. The measurements are supplemented by the vibrational spectra below 600 cm?1. Complex III crystallizes in the monoclinic space group P21/c with four formula units per unit cell. In addition, four molecules of CCl4 per unit cell are placed in cavities of the lattice. The refinement has been carried on to an R-value of 6.5%, taking into account 1 729 unique, observed reflexions. The structure consists of discrete molecules of [Ph2Cl2Sb(N2Me2CPh)], in which the antimony atoms are surrounded by the N atoms of the chelate ligand, the phenyl groups and the two axial Cl atoms in distorted octahedral arrangement. The planes of the phenyl rings form dihedral angles with the equatorial plane of 129° and 143°.  相似文献   

13.
The prototype dimeric chelating compounds 3,3′-methylenebis-[N(4-hydroxyphenyl) iminodiacetic acid] and 3,3′-methylenebis-[N(4-methoxyphenyl) iminodiacetic acid] were synthesized and characterized by composition analysis, infrared spectroscopy, and potentiometric titration data. Their chelating characteristics with Cu(II), Ni(II), Co(II), and Zn(l1) ions were established by composition analysis and comparative infrared spectroscopy.

The results suggest chelation and structures of the usual iminodiacetatometal complex type for the Ni(II), Co(II), and Zn(I1) compounds of 3,3′methylenebis-[N-(4-hydroxyphenyl) iminodiacetic acid] and for the Cu(I1, Ni(II), and Co(I1) compounds of 3,3′-methylenebis-[N-(4-methoxyphenyl) iminodiacetic acid]. The composition analysis of each of these compounds indicates 1:2:2 mole ratios of ligand to metal ion to water. Square planar structures are proposed wherein the two iminodiacetatometal chelate moieties are essentially independent of each other.

The composition analysis of the Cu(II) compound of 3,3′-methylenebis-[N-(4-hydroxyphenyl) iminodiacetic acid] indicates a 1:2:1 mole ratio of ligand to metal ion to water. Structures are proposed in which some of the carboxylate groups are bridges between two metal coordination centers.

The composition analysis of the Zn(II) compound of 3,3′-methylenebis-[N-(4-methoxyphenyl) iminodiacetic acid] indicates a 1:1 mole ratio of ligand to metal ion. A structure is proposed in which both nitrogen atoms and two of the four carboxylate groups of the dimeric ligand are coordinated to the same metal ion.

A preliminary investigation was made of oligomeric compounds analogous to the prototype dimeric compounds.  相似文献   

14.
Reaction of 2-(4'-R-phenylazo)-4-methylphenols (R = OCH3, CH3, H, Cl, and NO2) with [Ru(dmso)(4)Cl2]affords a family of five ruthenium(III) complexes, containing a 2-(arylazo)phenolate ligand forming a six-membered chelate ring and a tetradentate ligand formed from two 2-(arylazo)phenols via an unusual C-C coupling linking the two ortho carbons of the phenyl rings in the arylazo fragment. A similar reaction with 2-(2'-methylphenylazo)-4-methylphenol with [Ru(dmso)(4)Cl2] has afforded a similar complex, in which one 2-(2'-methylphenylazo)-4-methylphenolate ligand is coordinated forming a six-membered chelate ring, and the other two ligands have undergone the C-C coupling reaction, and the coupled species is coordinated as a tetradentate ligand forming a five-membered N,O-chelate ring, a nine-membered N,N-chelate ring, and another five-membered chelate ring. Reaction of 2-(2',6'-dimethylphenylazo)-4-methylphenol with [Ru(dmso)(4)Cl2] has afforded a complex in which two 2-(2',6'-dimethylphenylazo)-4-methylphenols are coordinated as bidentate N,O-donors forming five- and six-membered chelate rings, while the third one has undergone cleavage across the N=N bond, and the phenolate fragment, thus generated, remains coordinated to the metal center in the iminosemiquinonate form. Structures of four selected complexes have been determined by X-ray crystallography. The first six complexes are one-electron paramagnetic and show rhombic ESR spectra. The last complex is diamagnetic and shows characteristic 1H NMR signals. All the complexes show intense charge-transfer transitions in the visible region and a Ru(III)-Ru(IV) oxidation on the positive side of SCE and a Ru(III)-Ru(II) reduction on the negative side.  相似文献   

15.
The Crystal Structure of Bis(N,N-diethyl-N′ -benzoylselenoureato)nickel(II) Ni(C12H15N2OSe)2 crystallizes in the monoclinic space group P21/c. The cell parameters are a = 11.399(3), b = 16.016(4), c = 14.910(6) Å, β = 104.64(3)° and Z = 4. The structure was solved with Patterson and direct methods and was refined to a final R-value of 5.43%. Nickel is coordinated to two N,N-diethyl-N′ -benzoylselenourea molecules to form a bidentally coordinated chelate complex with cis arrangement of the donor atoms. Coordinaton around the nickel atom is planar while the chelate rings diverge from planarity. The ethyl groups of one diethylamino group are disordered. The Ni? Se bond lengths are 2.244(1) and 2.264(1) Å, the Ni? O bond lengths are 1.871(4) and 1.883(4) Å, respectively.  相似文献   

16.
Copper(II) complexes of peptides containing two or three histidyl residues (Ac-HisGlyHis-OH, Ac-HisGlyHis-NHMe, Ac-HisHisGlyHis-OH and Ac-HisHisGlyHis-NHMe) have been studied by potentiometric, UV-Vis, EPR and CD spectroscopic measurements. The imidazole nitrogen atoms are described as the primary metal binding sites of all ligands resulting in the formation of various macrochelates in the pH range 4 to 7. The (Nim, N-, Nim)-co-ordinated [CuH-1L]0+ complexes were mainly detected in samples containing free carboxylates at the C-termini, whilst the [CuH-2L]-(0) complexes were the predominant species in slightly alkaline solution and their binding modes were described via 4N-co-ordination (Nim, N-, N-, Nim) in (7,5,6)-membered fused chelate rings. Deprotonation and co-ordination of the third amide nitrogens were detected above pH approximately 9 in all cases.  相似文献   

17.
Abstract

The occurence of isoproturon [N-(4-isopropylphenyl)-N′, N′-dimethyl urea] and its metabolites was investigated in soil solution, runoff and creek water from a farm in Scheyern (Bavaria, FRG) after a heavy rainfall event following the application in spring 1994. The analytical procedure included enrichment by C 18 solid-phase extraction and reversed-phase HPLC with diode array detection. The major degradation product in most of the samples was identified as 2-hydroxy-isoproturon [N-(4-(2-hydroxyisopropyl)-phenyl)-N′. N′ dimethyl urea] using the authentic compound. The latter has been isolated from wheat cell culture medium and its structure elucidated by NMR and MS. Furthermore, the polar metabolites monodesmethyl-isoproturon [N-′ (4-Isopropylphenyl)-N′-methyl urea] and 2-hydroxy-monodesmethyl-isoproturon [N-(4-Isopropylphenyl)-N′-methyl urea] and 2-hydroxy-monodesmethyl-isoproturon [N-(4-(2-hydroxyisopropyl)-phenyl)-N′-methyl urea] were identified by comparison of their retention times and DAD-UV spectra with reference compounds.

The detection of isoproturon in soil solution down to 170 cm depth and in creek water in concentrations exceeding 4 μg/1 and also of the polar metabolites in concentrations up to 0,9 μg/1 indicated the mobility of this phenylurea herbicide and its degradation products. Therefore the metabolites should be considered in studies on the migration of isoproturon and in the ecotoxicological evaluation.  相似文献   

18.
Crystal and Molecular Structure of Bis(N, N-diethyl-2-benzoylthioacetamidato)copper(II) Bis(N, N-diethyl-2-benzoyl-thioacetamidato)copper(II) has been investigated by X-ray structure analysis. It crystallizes in the triclinic space group P1 with a = 10.709, b = 12.150, c = 15.651 Å, α = 90.13, β = 103.73, γ = 98.30° and with 3 formula units per unit cell. The structure was solved by heavy atom technique. The final R value was 0.04 for 4151 symmetry independent reflections. The crystal contains two symmetry independent molecules. One of them shows a nearly planar cis-arrangement of the ligator atoms but the other has an exactly planar trans-arrangement. The chelate rings show a distorted planarity in both molecules. The results of the structure determination confirm the conclusions from the EPR crystal spectrum.  相似文献   

19.
The hitherto unreported compounds of general structure 3,3′-(alkanediyl)bis-(2,2,2-triaryl-1-oxa-2-stiba-3-azabenzo[d]cyclohex-5-ene) have been synthesized in 48-56% yields by the cyclization of the tetrasodium salt of N,N′-bis(2-hydroxybenzyl)-1,2-diaminoethane(II) or of N,N′-bis(2-hydroxybenzyl)-1,3-diaminopropane(II*) with R3SbBr2 (R = phenyl, p-tolyl, or mesityl). The tetrasodium salts were prepared by the reactions of the corresponding amines with sodium hydride. The amines (II and II*), in turn, were obtained by the sodium borohydride reduction of N,N′-bis(salicylidene)-1,2-diaminoethane and N,N′-bis-(salicylidene)-1,3,-diaminopropane, respectively. The heterocyclic compounds are air stable and moisture insensitive. These compounds have been characterized by elemental analyses, molecular weight determinations, and by IR, far IR, 1H, and 13C NMR spectral studies. © 1996 John Wiley & Sons, Inc.  相似文献   

20.
以苊为原料,经硝化、氧化、缩合和取代反应合成了以萘酰亚胺作为分子荧光基团,脲作为识别基团的新型荧光化学传感器分子——N-{4-[6-硝基-1,3-二酮-1H-苯并[de]异喹啉-2(3H)-基]苯基}-N′-苯基脲(1),其结构经1HNMR和IR表征。运用荧光滴定法测试了1对阴离子(F-,Cl-,Br-和I-)的识别能力。结果表明,1对F-具有较好的选择识别性能。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号