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1.
Pawlak T Pazderski L Sitkowski J Kozerski L Szłyk E 《Magnetic resonance in chemistry : MRC》2011,49(2):59-64
(1)H, (13)C, (195)Pt and (15)N NMR studies of platinide(II) (M = Pd, Pt) chloride complexes with such alkyl and aryl derivatives of 2,2'-bipyridine and 1,10-phenanthroline as LL = 6,6'-dimethyl-bpy, 5,5'-dimethyl-bpy, 4,4'-di-tert-butyl-bpy, 2,9-dimethyl-phen, 2,9-dimethyl-4,7-diphenyl-phen, 3,4,7,8-tetramethyl-phen, having the general [M(LL)Cl(2)] formula were performed and the respective chemical shifts (δ(1H), δ(13C), δ(195Pt), δ(15N)) reported. (1)H high-frequency coordination shifts (Δ(coord)(1H) = δ(complex)(1H)-δ(ligand)(1H)) mostly pronounced for nitrogen-adjacent protons and methyl groups in the nearest adjacency of nitrogen, as well as (15)N low-frequency coordination shifts (Δ(coord)(15H) = δ(complex)(15H)-δ(ligand)(15H)) were discussed in relation to the molecular structures. 相似文献
2.
Pazderski L Tousek J Sitkowski J Kozerski L Szłyk E 《Magnetic resonance in chemistry : MRC》2007,45(12):1045-1058
1H, 13C and 15N NMR studies of platinide(II) (M=Pd, Pt) chloride complexes with methyl and phenyl derivatives of 2,2'-bipyridine and 1,10-phenanthroline [LL=4,4'-dimethyl-2,2'-bipyridine (dmbpy); 4,4'-diphenyl-2,2'-bipyridine (dpbpy); 4,7-dimethyl-1,10-phenanthroline (dmphen); 4,7-diphenyl-1,10-phenanthroline (dpphen)] having a general [M(LL)Cl2] formula were performed and the respective chemical shifts (delta1H, delta13C, delta15N) reported. 1H high-frequency coordination shifts (Delta1Hcoord=delta1Hcomplex-delta1Hligand) were discussed in relation to the changes of diamagnetic contribution in the relevant 1H shielding constants. The comparison to literature data for similar [M(LL)(XX)], [M(LL)X2] and [M(LL)XY] coordination or organometallic compounds containing various auxiliary ligands revealed a large dependence of delta1H parameters on inductive and anisotropic effects. 15N low-frequency coordination shifts (Delta15Ncoord=delta 15Ncomplex-delta15Nligand) of ca 88-96 ppm for M=Pd and ca 103-111 ppm for M=Pt were attributed to both the decrease of the absolute value of paramagnetic contribution and the increase of the diamagnetic term in the expression for 15N shielding constants. The absolute magnitude of Delta15Ncoord parameter increased by ca 15 ppm upon Pd(II)-->Pt(II) transition and by ca 6-7 ppm following dmbpy-->dmphen or dpbpy-->dpphen ligand replacement; variations between analogous complexes containing methyl and phenyl ligands (dmbpy vs dpbpy; dmphen vs dpphen) did not exceed+/-1.5 ppm. Experimental 1H, 13C, 15N NMR chemical shifts were compared to those quantum-chemically calculated by B3LYP/LanL2DZ+6-31G**//B3LYP/LanL2DZ+6-31G*, both in vacuo and in DMSO or DMF solution. 相似文献
3.
Ring current and proximity effects may be responsible for both low‐ and high‐frequency shifts of the aromatic protons of Ru coordinated bipyridyls according to the different geometries depending on whether two or three bipyridyls are coordinated. Copyright © 2003 Crown in the right of Canada. Published by John Wiley & Sons, Ltd. 相似文献
4.
Leszek Pazderski Jaromír Touek Andrzej Wojtczak Jerzy Sitkowski Lech Kozerski Edward Szyk 《Polyhedron》2008,27(14):3067-3078
The crystal and molecular structure of potassium aquapentachloroiridate(III) (K2[Ir(H2O)Cl5]) was reported. The [Ir(H2O)Cl5]2− anions are nearly octahedral, the axial Ir–Cl bond (2.322(2) Å) being shorter than the equatorial ones (2.346(2)–2.360(2) Å); the Ir–O bond length is 2.090(4) Å. Ir(III) chloride complexes with 2,2′-bipyridine (LL = bpy) or 1,10-phenanthroline (LL = phen), of the general formulae K[Ir(LL)Cl4] and cis-[Ir(LL)2Cl2]Cl, were studied by far-IR and 1H–13C, 1H–15N HMBC/HMQC/HSQC–NMR. High-frequency 1H NMR coordination shifts (Δ1Hcoord = δ1Hcomplex − δ1Hligand; max. ca. +1 ppm) were noted for [Ir(LL)Cl4]− anions, while for cis-[Ir(LL)2Cl2]+ cations they had variable sign and magnitude (max. ca. ±1 ppm); they were dependent on the proton position, being mostly expressed for the nitrogen-adjacent hydrogens (H(6) for bpy, H(2) for phen). 13C NMR signals were high-frequency shifted (by max. ca. 8 ppm), whereas all 15N nuclei were shifted to the lower frequency (by ca. 105–120 ppm). The experimental 1H, 13C, 15N NMR chemical shifts were reproduced by semi-empirical quantum-chemical calculations (B3LYP/LanL2DZ+6-31G**//B3LYP/LanL2DZ+6-31G*). 相似文献
5.
Yu‐Xiu Jin Fang Yang Li‐Min Yuan Chao‐Guo Yan Wen‐Long Liu 《Acta Crystallographica. Section C, Structural Chemistry》2014,70(5):517-521
In poly[[μ3‐2,2′‐(disulfanediyl)dibenzoato‐κ5O:O,O′:O′′,O′′′](1,10‐phenanthroline‐κ2N,N′)cadmium(II)], [Cd(C14H8O4S2)(C12H8N2)]n, the asymmetric unit contains one CdII cation, one 2,2′‐(disulfanediyl)dibenzoate anion (denoted dtdb2−) and one 1,10‐phenanthroline ligand (denoted phen). Each CdII centre is seven‐coordinated by five O atoms of bridging/chelating carboxylate groups from three dtdb2− ligands and by two N atoms from one phen ligand, forming a distorted pentagonal–bipyramidal geometry. The CdII cations are bridged by dtdb2− anions to give a two‐dimensional (4,4) layer. The layers are stacked to generate a three‐dimensional supramolecular architecture via a combination of aromatic C—H...π and π–π interactions. The thermogravimetric and luminescence properties of this compound were also investigated. 相似文献
6.
《Electroanalysis》2003,15(18):1460-1464
The electroactive composite containing tris(2,2′‐bipyridine) ruthenium(II) and 12‐molybdophosphate (RuPMo12) was synthesized and first used as a bifunctional electrocatalyst to fabricate a chemically bulk‐modified carbon paste electrode (RuPMo12‐CPE) by direct mixing. The electrochemical behavior of the RuPMo12‐CPE was studied by cyclic voltammetry. The RuPMo12‐CPE presents good electrocatalytic activity not only toward the reduction of hydrogen peroxide and bromate, which is attributed to the function of molybdophosphate, but also toward the oxidation of arsenite, which is primarily attributed to the function of tris(2,2′‐bipyridine) ruthenium(II). The remarkable advantage of the RuPMo12‐CPE is its good stability owing to the insolubility of RuPMo12 and reproducibility of surface renewal. 相似文献
7.
The syntheses, characterizations and in vitro cytotoxities of seven soluble silver (I) compounds (1–7) with 2,2′‐bipyridine (bpy), 5,5′‐dimethyl‐2,2′‐bipyridine (dmbpy) and 1, 10‐phenanthroline (phen) are described. Two of the complexes, [Ag(dmbpy)(NO3)] (1) and [Ag(dmbpy)]ClO4(2), have been structurally established by single‐crystal X‐ray diffraction, which reveals the silver(I) atom in compound 1 is in a Y‐shape coordination geometry with two N atoms (av. Ag? N = 227.8 pm) from a chelate dmbpy ligand and an O atom (Ag? O=221.8(4) pm) from a monodentate nitrate. The Ag(I) atom in compound 2 is three‐coordinated by three N atoms, two of which are from a chelate dmbpy, and one from an acetonitrile ligand. The seven compounds showed strong cytotoxities in vitro to both normal and carcinoma cells. 相似文献
8.
A two‐dimensional copper(II) coordination polymer based on 2,4′‐oxybis(benzoate) and 4,4′‐bipyridine
《Acta Crystallographica. Section C, Structural Chemistry》2017,73(7):503-507
The reaction of Cu(NO3)2·3H2O with 2,4′‐oxybis(benzoic acid) and 4,4′‐bipyridine under hydrothermal conditions produced a new mixed‐ligand two‐dimensional copper(II) coordination polymer, namely poly[[(μ‐4,4′‐bipyridine‐κ2N ,N ′)[μ‐2,4′‐oxybis(benzoato)‐κ4O 2,O 2′:O 4,O 4′]copper(II)] monohydrate], {[Cu(C14H8O5)(C10H8N2)]·H2O}n , which was characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis and single‐crystal X‐ray diffraction. The X‐ray diffraction crystal structure analysis reveals that the CuII ions are connected to form a two‐dimensional wave‐like network through 4,4′‐bipyridine and 2,4′‐oxybis(benzoate) ligands. The two‐dimensional layers are expanded into a three‐dimensional supramolecular structure through intermolecular O—H…O and C—H…O hydrogen bonds. Furthermore, magnetic susceptibility measurements indicate that the complex shows weak antiferromagnetic interactions between adjacent CuII ions. 相似文献
9.
《Helvetica chimica acta》2018,101(5)
Heteroleptic Ru(II) complexes were designed based on 4,4′‐bis((E)‐styryl)‐2,2′‐bipyridine (bsbpy) as an ancillary ligand for dye‐sensitized solar cells (DSSCs), and those Ru(II) sensitizers, [Ru(L)(bsbpy)(NCS)2][TBA] (TBA; tetrabutylammonium), were synthesized according to a typical one‐pot reaction of [RuCl2(p‐cymene)]2 with the corresponding anchoring ligands (where L = 4,4′‐dicarboxy‐2,2′‐bipyridine (dcbpy), 4,4′‐bis((E)‐carboxyvinyl)‐2,2′‐bipyridine (dcvbpy), 4,7‐dicarboxy‐1,10‐phenanthroline (dcphen), or 4,7‐bis((E)‐carboxyvinyl)‐1,10‐phenanthroline (dcvphen)). The new Ru(II) dyes, [Ru(L)(bsbpy)(NCS)2][TBA] that incorporated vinyl spacer(s) into ancillary and/or anchoring ligand displayed red‐shifted bands over the overall UV/VIS region relative to the absorption spectra of N719 . A combination of bsbpy ancillary and dcphen anchoring ligand showed the best result for the overall power conversion efficiency (η); i.e., a DSSC fabricated with [Ru(dcphen)(bsbpy)(NCS)2][TBA] exhibited a power conversion efficiency (η) of 2.98% (compare to N719 , 4.82%). 相似文献
10.
Nabanita Kundu Debdas Mandal Muktimoy Chaudhury Edward R. T. Tiekink 《应用有机金属化学》2005,19(12):1268-1270
The photoluminescence characteristics of the [Cd(bipy)3][PF6]2 complex are reported. A moderately large quantum yield (φ) of 1.07 × 10?2 is exhibited in acetonitrile solution at 298 K. Crystallography shows the dication to have a distorted octahedral geometry and the crystal structure to be stabilized by C? H···π and C? H···F interactions. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
11.
Leszek Pazderski Tomasz Pawlak Jerzy Sitkowski Lech Kozerski Edward Szłyk 《Magnetic resonance in chemistry : MRC》2010,48(6):417-426
1H, 13C and 15N NMR studies of gold(III), palladium(II) and platinum(II) chloride complexes with dimethylpyridines (lutidines: 2,3‐lutidine, 2,3lut; 2,4‐lutidine, 2,4lut; 3,5‐lutidine, 3,5lut; 2,6‐lutidine, 2,6lut) and 2,4,6‐trimethylpyridine (2,4,6‐collidine, 2,4,6col) having general formulae [AuLCl3], trans‐[PdL2Cl2] and trans‐/cis‐[PtL2Cl2] were performed and the respective chemical shifts (δ1H, δ13C, δ15N) reported. The deshielding of protons and carbons, as well as the shielding of nitrogens was observed. The 1H, 13C and 15N NMR coordination shifts (Δ1Hcoord, Δ13Ccoord, Δ15Ncoord; Δcoord = δcomplex ? δligand) were discussed in relation to some structural features of the title complexes, such as the type of the central atom [Au(III), Pd(II), Pt(II)], geometry (trans‐ or cis‐), metal‐nitrogen bond lengths and the position of both methyl groups in the pyridine ring system. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
12.
Electrochemiluminescence (ECL) of tris(2,2′‐bipyridine)ruthenium, Ru(bpy)32+ in the presence of various co‐reactants, such as tripropylamine (TPA), oxalate ion (C2O42?), ascorbic acid (H2A) and dehydroascorbic acid (DHA), were investigated under ultrasound irradiation. In sono‐ECL experiments, an indium‐thin‐oxide (ITO) was used as working electrode, and a titanium tipped sonic horn probe (diameter 2 mm) which operated at a frequency of 20 kHz was set in the front of the ITO electrode. Under the ultrasound irradiation, ECL signals were found to be significantly enhanced when TPA and C2O42? were used as co‐reactants, only slightly enhanced in Ru(bpy)32+/DHA system, but total quenched in Ru(bpy)32+/H2A system. The difference of Ru(bpy)32+ ECL behaviors for various co‐reactant could to be due to the different kinetics of catalytic reactions associated in ECL schemes. ECL quenching effect observed in Ru(bpy)32+/H2A system was suggested to be due to electron transfer (ET) route between the excited state *Ru(bpy)32+ and ascorbate anion HA? diffused from the bulk solution, where the diffusional HA? species served as electron donor. The effect becomes more pronounced upon sonication because the effective collision frequency between *Ru(bpy)32+ and HA? would be significantly increased by the enhanced mass transport effect of ultrasound. 相似文献
13.
Two transition metal‐organic coordination polymers, [Mn2(1,3‐bdc)2(Me2bpy)2] · Me2bpy ( 1 ) and [Co(4,4′‐oba)(Me2bpy)] ( 2 ) were hydrothermally synthesized and structurally characterized by elemental analysis, IR spectroscopy, TG, and single‐crystal X‐ray diffraction [1,3‐H2bdc = benzene‐1,3‐dicarboxylic acid, H2oba = 4,4′‐oxybis(benzoic acid) Me2bpy = 4,4′‐dimethyl‐2,2′‐bipyridine]. Compound 1 crystallizes in the orthorhombic system, space group P212121, with a = 23.371(5), b = 14.419(3), and c = 14.251(3) Å. Compound 2 crystallizes in the monoclinic system, space group P21/c, with a = 7.4863(15), b = 18.272(4), c = 16.953(5) Å, and β = 107.44(3)°. The crystal structure of complex 1 is a wave‐like layer with central Mn2+ atoms bridged by 1,3‐bdc ligands, whereas the structure of compound 2 presents a ladder chain of hexacoordinate Co2+ atoms, in which the metal atoms are bridged by 4,4′‐oba ligands and decorated by Me2bpy ligands. The two compounds are further extended into 3D supramolecular structures through π–π stacking interactions. Additionally, the compounds show intense fluorescence in solid state at room temperature. 相似文献
14.
Pazderski L Tousek J Sitkowski J Kozerski L Marek R Szłyk E 《Magnetic resonance in chemistry : MRC》2007,45(1):24-36
Au(III), Co(III) and Rh(III) chloride complexes with pyridine (py), 2,2'-bipyridine (bpy) and 1,10-phenanthroline (phen) of the general formulae [M1LCl3], trans-[M2L4Cl2]+, mer-[M2L3Cl3], [M1(LL)Cl2]+, cis-[M2(LL)2Cl2]+, where M1=Au; M2=Co, Rh; L=py; LL=bpy, phen, were studied by 1H--13C HMBC and 1H--15N HMQC/HSQC. The 1H, 13C and 15N coordination shifts (the latter from ca-78 to ca-107 ppm) are discussed in relation to the type of metal, electron configuration, coordination sphere geometry and the type of ligand. The 13C and 15N chemical shifts were also calculated by quantum-chemical NMR methods, which reproduced well the experimental tendencies concerning the coordination sphere geometry and the ligand type. 相似文献
15.
André Grüßing Sven Rau Sebastian Schebesta Alexander Scholz Helmar Görls Dirk Walther Prof. Dr. 《无机化学与普通化学杂志》2007,633(7):961-970
Syntheses and Structures of Bis(4,4′‐t‐butyl‐2,2′‐bipyridine) Ruthenium(II) Complexes with functional Derivatives of Tetramethyl‐bibenzimidazole [(tbbpy)2RuCl2] reacts with dinitro‐tetramethylbibenzimidazole ( A ) in DMF to form the complex [(tbbpy)2Ru( A )](PF6)2 ( 1a ) (tbbpy: bis(4,4′‐t‐butyl)‐2,2′bipyridine). Exchange of the two PF6? anions by a mixture of tetrafluor‐terephthalat/tetrafluor‐terephthalic acid results in the formation of 1b in which an extended hydrogen‐bonded network is formed. According to the 1H NMR spectra and X‐ray analyses of both 1a and 1b , the two nitro groups of the bibenzimidazole ligand are situated at the periphery of the complex in cis position to each other. Reduction of the nitro groups in 1a with SnCl2/HCl results in the corresponding diamino complex 2 which is a useful starting product for further functionalization reactions. Substitution of the two amino groups in 2 by bromide or iodide via Sandmeyer reaction results in the crystalline complexes [(tbbpy)2Ru( C )](PF6)2 and [(tbbpy)2Ru( D )](PF6)2 ( C : dibromo‐tetrabibenzimidazole, D : diiodo‐tetrabibenzimidazole). Furthermore, 2 readily reacts with 4‐t‐butyl‐salicylaldehyde or pyridine‐2‐carbaldehyde under formation of the corresponding Schiff base RuII complexes 5 and 6 . 1H NMR spectra show that the substituents (NH2, Br, I, azomethines) in 2 ‐ 6 are also situated in peripheral positions, cis to each other. The solid state structure of both 2 , and 3 , determined by X‐ray analyses confirm this structure. In addition, the X‐ray diffraction analyses of single crystals of the complexes [(tri‐t‐butyl‐terpy)(Cl)Ru( A )] ( 7 ) and [( A )PtCl2] ( 8 ) display also that the nitro groups in these complexes are in a cis‐arrangement. 相似文献
16.
Yuan-Chun He Li-Yuan Xiao Zi-Han Yuan Jie Zhang Yan Wang Na Xu 《Acta Crystallographica. Section C, Structural Chemistry》2019,75(12):1562-1568
Coordination polymers (CPs) have attracted increasing interest in recent years. In this work, two new CPs, namely poly[[aquabis(2,2′‐bipyridine‐κ2N,N′){μ3‐5‐[(4‐carboxylatophenoxy)methyl]benzene‐1,3‐dicarboxylato‐κ4O1,O1′:O3:O5}(μ‐formato‐κ3O:O,O′)dicadmium(II)] monohydrate], {[Cd2(C16H9O7)(HCO2)(C10H8N2)2(H2O)]·H2O}n ( 1 ), and poly[[(2,2′‐bipyridine‐κ2N,N′){μ3‐5‐[(4‐carboxylphenoxy)methyl]benzene‐1,3‐dicarboxylato‐κ4O1,O1′:O3:O5}manganese(II)] sesquihydrate], {[Mn(C16H10O7)(C10H8N2)]·1.5H2O}n ( 2 ), have been prepared using the tricarboxylic acid 5‐[(4‐carboxyphenoxy)methyl]benzene‐1,3‐dicarboxylic acid and 2,2′‐bipyridine under hydrothermal conditions. CP 1 displays a two‐dimensional layer structure which is further extended into a three‐dimensional (3D) supramolecular structure via intermolecular π–π interactions, while CP 2 shows a different 3D supramolecular structure extended from one‐dimensional ladder chains by intermolecular π–π interactions. In addition, the solid‐state luminescence spectra of 1 and 2 were studied at room temperature. 相似文献
17.
Leszek Pazderski Jaromír Toušek Jerzy Sitkowski Kateřina Maliňáková Lech Kozerski Edward Szłyk 《Magnetic resonance in chemistry : MRC》2009,47(3):228-238
1H, 13C and 15N NMR studies of gold(III), palladium(II) and platinum(II) chloride complexes with picolines, [Au(PIC)Cl3], trans‐[Pd(PIC)2Cl2], trans/cis‐[Pt(PIC)2Cl2] and [Pt(PIC)4]Cl2, were performed. After complexation, the 1H and 13C signals were shifted to higher frequency, whereas the 15N ones to lower (by ca 80–110 ppm), with respect to the free ligands. The 15N shielding phenomenon was enhanced in the series [Au(PIC)Cl3] < trans‐[Pd(PIC)2Cl2] < cis‐[Pt(PIC)2Cl2] < trans‐[Pt(PIC)2Cl2]; it increased following the Pd(II) → Pt(II) replacement, but decreased upon the trans → cis‐transition. Experimental 1H, 13C and 15N NMR chemical shifts were compared to those quantum‐chemically calculated by B3LYP/LanL2DZ + 6‐31G**//B3LYP/LanL2DZ + 6‐31G*. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
18.
Two new complexes: [Cu(TBZ)(bipy)Cl]Cl·H2O ( 1 ) and [Cu(TBZ)(phen)Cl]Cl·H2O ( 2 ) [TBZ=2‐(4′‐thiazolyl)‐ benzimidazole, phen=1,10‐phenanthroline and bipy=2,2′‐bipyridine] have been synthesized and characterized by elemental analysis, molar conductivity, IR, and UV‐vis methods. Complex 2 , structurally characterized by single‐crystal X‐ray crystallography, crystallizes in the monoclinic space group P21/c in a unit cell of a=0.85257(12) nm, b=2.5358(4) nm, c=1.15151(13) nm, β=118.721(8)°, V=2.183.2(5) nm3, Z=4, Dc=1.624 g·cm−3, µ=1.367 mm−1. The complexes, free ligands and chloride copper(II) salt were each tested for their ability to inhibit the growth of two gram‐positive (B. subtilis and S. aureus) and two gram‐negative (Salmonella and E. coli) bacteria. The complexes showed good antibacterial activities against the microorganisms. The interaction between the complexes and calf thymus DNA in aqueous solution was investigated adopting electronic absorption spectroscopy, fluorescence spectroscopy, viscosity measurements and cyclic voltammetry. Results suggest that the two complexes can bind to DNA by intercalative mode. In addition, the result of agarose gel electrophoresis suggested that the complexes can cleave the plasmid DNA at physiological pH and room temperature. Mechanistic studies with different inhibiting reagents reveal that hydroxyl radicals, and a singlet oxygen‐like copper‐oxo species are all involved in the DNA scission process mediated by the complexes. 相似文献
19.
Pazderski L Tousek J Sitkowski J Kozerski L Szłyk E 《Magnetic resonance in chemistry : MRC》2007,45(12):1059-1071
1H, 13C, and 15N NMR studies of platinide(II) (M=Pd, Pt) chloride complexes with quinolines (L=quinoline-quin, or isoquinoline-isoquin; LL=2,2'-biquinoline-bquin), having the general formulae trans-/cis-[ML2Cl2] and [M(LL)Cl2], were performed and the respective chemical shifts (delta1H, delta13C, delta15N) reported. 1H coordination shifts of various signs and magnitudes (Delta1Hcoord=delta1Hcomplex-delta1Hligand) are discussed in relation to the changes of diamagnetic contribution to the relevant 1H shielding constants. The comparison to the literature data for similar complexes containing auxiliary ligands other than chlorides exhibited a large dependence of delta1H parameters on electron density variations and ring-current effects (inductive and anisotropic phenomena). The influence of deviations from planarity, concerning either MN2Cl2 chromophores or azine ring systems, revealed by the known X-ray structures of [Pd(bquin)Cl2] and [Pt(bquin)Cl2], is discussed in respect to 1H NMR spectra. 15N coordination shifts (Delta15Ncoord=delta15Ncomplex-delta15Nligand) of ca. 78-100 ppm (to lower frequency) are attributed mainly to the decrease of the absolute value of paramagnetic contribution in the relevant 15N shielding constants, this phenomenon being noticeably dependent on the type of a platinide metal and coordination sphere geometry. The absolute magnitude of Delta15Ncoord parameter increased by ca 15 ppm upon Pd(II)-->Pt(II) replacement but decreased by ca. 15 ppm following trans-->cis transition. Experimental 1H, 13C, 15N NMR chemical shifts are compared to those quantum-chemically calculated by B3LYP/LanL2DZ+6-31G**//B3LYP/LanL2DZ+6-31G*, both in vacuo and in CHCl3 or DMF solution. 相似文献
20.
Novel 4,4′‐dichloro‐2,2′‐[ethylenedioxybis(nitrilomethylidyne)]diphenol (H2L) and its complexes [CuL] and {[CoL(THF)]2(OAc)2Co} have been synthesized and characterized by elemental analyses, IR, 1H‐NMR and X‐ray crystallography. [CuL] forms a mononuclear structure which may be stabilized by the intermolecular contacts between copper atom (Cu) and oxygen atom (O3) to form a head‐to‐tail dimer. In {[CoL(THF)]2(OAc)2Co}, two acetates coordinate to three cobalt ions through Co? O? C? O? Co bridges and four µ‐phenoxo oxygen atoms from two [CoL(THF)] units also coordinate to cobalt ions. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献