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1.
P. Byabartta 《Russian Journal of Coordination Chemistry》2009,35(8):582-587
The hetero-tris-chelates of the formula [Ru(Phen)(RAaiR′)2](ClO4)2 (Phen = 1,10-phenanthroline, RAaiR′ = 1-alkyl-2-(arylazo)imidazole, p-R-C6H4-N=N-C3H2-NN-1-R′, where R = H (a), Me (b), Cl (c) and R′ = Me (II), Et (III), CH2Ph (IV)) have been isolated from the reaction of ctc-[RuCl2(RAaiR′)2] with AgNO3 + Phen or [Ag(Phen)2](ClO4) in acetone at 40°C in dark followed by the addition of NaClO4 (aq). The stereo-chemistry of the complexes have been supported by 1H NMR data. Considering the arylazoimidazole and phenanthroline moietie there are twenty different carbon atoms in the molecule
which gives a total of twenty different peaks in the 13C NMR spectrum of complex Ia. Cyclic voltammograms show Ru(III)/Ru(II) couple at 1.3–1.4 V vs SCE along with three successive ligand reductions.
The article is published in the original. 相似文献
2.
Seikh Jasimuddin 《Transition Metal Chemistry》2006,31(6):724-729
Dechlorination of M(RaaiR′)
n
Cl2 by AgNO3 produced [M(RaaiR′)
n
(MeCN)2]+2 [M = Ru(II), n = 2; Pt(II), n = 1; RaaiR′ = 1-alkyl-2-(arylazo)imidazole)] which upon reaction with the nucleobase cytosine (C) in MeCN solution gave cytosinato
bridged dimeric compounds which were isolated as perchlorate salts [M2(RaaiR′)
n
(C)2](ClO4)2 · H2O. The products were characterized by IR, u.v.–vis., 1H-n.m.r. spectroscopy and cyclic voltammetry. In MeCN solution the ruthenium complexes exhibit a strong MLCT band at 550–555 nm
and two redox couples positive to SCE due to two metal-center oxidation along with ligand reduction, negative to SCE. The
platinum complexes show a weak transition at 500–520 nm in MeCN and exhibit only ligand reduction in cyclic voltammetry. The
coordination of the ligand was supported by 1H-n.m.r. spectral data. 相似文献
3.
Prasenjit Bhunia Bhulendranath Baruri Umasankar Ray Chittaranjan Sinha Sunirban Das Jack Cheng Tian-Huey Lu 《Transition Metal Chemistry》2006,31(3):310-315
The reaction of Mn(OAc)2 · 4H2O and 1-alkyl-2-(arylazo)imidazole [RaaiR′ where R = H (a), Me (b); R′ = Me (1/3/), Et (2/4/)] and NH4NCS in MeOH in a 1:2:2 mole ratio afforded [Mn(RaaiR′)2(NCS)2] (3) and (4) complexes. They were characterized by different physicochemical methods and the structure has been confirmed by single crystal
X-ray diffraction study for title compound. One of the primary ligands was also characterised by an X-ray diffraction study. 相似文献
4.
P. Byabartta 《Russian Journal of Coordination Chemistry》2009,35(9):687-691
Silver-assisted aquation of blue cis-trans-cis-RuCl2(RAaiR’)2 (I) leads to the synthesis of solvento species, blue-violet cis-trans-cis-[Ru(OH2)2(RAaiR’)2](ClO4)2 (II), where RAaiR’ = p-R-C6H4-N=N-C3H2-NN, abbreviated as N,N′ chelator (N(imidazole) and N(azo) represent N and N′, respectively); R = H (a), p-Me (b), p-Cl(c); R′ = Me (III), Et (IV), Bz (V), that reacted with NCS− in warm EtOH resulting in red-violet dithiocyanato complexes of the type [Ru(NCS)2(RAaiR)2] (IIIa–Vn). These complexes were studied by elemental analysis, UV-Vis, IR, and 1H NMR spectroscopy and cyclic voltammetry. The solution structure and stereoretentive transformation in each step have been
established from 1H NMR results. All the complexes exhibit strong MLCT transitions in the visible region. They are redox active and display
one metal-centered oxidation and successive ligand-based reductions. Linkage isomerisation was studied by changing the solvent
and then by UV-Vis spectral analysis. 相似文献
5.
Two copper(I) complexes [Cu(Cin2bda)2]ClO4 (I) and [Cu(Ncin2bda)2]ClO4 (II) have been prepared by the reaction of the ligands N2,N2′-bis(3-phenylallylidene)biphenyl-2,2′-diamine (L1) and N2,N2′-bis[3-(2-nitrophenyl)allylidene]biphenyl-2,2′-diamine (L2) and copper(I) salt. These compounds were characterized by CHN analyses, 1H NMR, IR, and UV-Vis spectroscopy. The C=N stretching frequency in the copper(I) complexes shows a shift to a lower frequency
relative to the free ligand due to the coordination of the nitrogen atoms. The crystal and molecular structure of II was determined
by X-ray single-crystal crystallography. The coordination polyhedron about the copper(I) center in the complex is best described
as a distorted tetrahedron. A quasireversible redox behavior was observed for complexes I and II.
The article is published in the original. 相似文献
6.
A semi-rigid bipyrazolyl ligand, namely 5-tert-butyl-1,3-bis[(3′,5′-diethyl-1H-pyrazol-4′-yl) methylene]benzene, and its Ag(I) and Cu(II) complexes have been prepared and structurally characterized. X-ray
analysis demonstrates that the Ag(I) complex is based on a dinuclear molecular rectangle, while the Cu(II) complex displays
a mono-strand helical structure. Two different conformations, namely cis,cis and cis,trans have been observed for this bipyrazolyl ligand. 相似文献
7.
Jing-Lin Chen Bo Wu Wei Gu Xing-Fu Cao He-Rui Wen Ruijin Hong Jinsheng Liao Bo-Tao Su 《Transition Metal Chemistry》2011,36(4):379-385
The mono- and dinuclear Cu(I) complexes [CuI(PPh3)(pmtz)] (1) and [{Cu(PPh3)2}2(μ-pmtz)](ClO4)2 (2), where pmtz is 3-(2-pyrimidinyl)-1,2,4-triazine, have been synthesized and characterized. Single-crystal X-ray diffraction
analysis reveals that the pmtz acts as a bidentate ligand in complex 1, whereas in complex 2 the pmtz coordinates as a bis-bidentate chelate, assembling two identical {Cu(PPh3)2} moieties into a copper(I) dimer with a triple-decker sandwich structure involving phenyl/pmtz/phenyl π–π interactions. The
UV–vis spectra of complexes 1 and 2 show low-energy absorptions at 350–550 nm, assigned to the Cu(I) to pmtz MLCT transition, probably mixed with some XLCT character
for 1. The absorption of 2 is blue-shifted relative to that of 1 due to the substitution of the iodide of 1 with the π-acceptor ligand PPh3. Complexes 1 and 2 are non-emissive, both in solution and in the solid state, most likely owing to the electronic effects induced by the additional
nitrogen donor of pmtz compared to 2,2′-bipyrimidine. 相似文献
8.
Stephanie S. Peterson Tishal Kirby Mariappan Kadarkaraisamy Richard M. Hartshorn Andrew G. Sykes 《Polyhedron》2009,28(14):3031-3035
Reaction of Ag(I) and Cu(I) [M(NCCH3)4]X (X = BF4− and PF6−) salts with 1,8-bis(nicotinyloxy)anthracene-9,10-dione (1), 1,8-bis(isonicotinyloxy)anthracene-9,10-dione (2), and 1,8-bis(pyrimidine-5-carboxyloxy)anthracene-9,10-dione (3), yield new chelating and bridging complexes and two new coordination polymers. The bridging capabilities of ligands 1 and 2 have not been demonstrated before, and ligand 1, by itself, has the flexibility to produce either chelated or bridged structures and an unusual ladder coordination polymer. The tetradentate ligand 3 also produces a one-dimensional coordination polymer in the presence of one equivalent of Ag(I). All complexes have been characterized by X-ray crystallography. 相似文献
9.
Zhao-Yang Wang Jing-Huo Chen Ling-Fei Zhao Wen-Hua Zhang Guang Yang 《Transition Metal Chemistry》2011,36(7):731-737
Two semi-rigid bipyrazolyl ligands, namely 2,3,5,6-tetramethyl-1,4-bis[(3′,5′-dimethyl-1H -pyrazol-4′-yl)methylene]benzene (H2L) and 2,3,5,6-tetramethyl-1,4-bis[(3′,5′-diphenyl-1H -pyrazol-4′-yl)methylene]benzene (H2L′), and their Ag(I) and Cu(II) complexes have been prepared and structurally characterized by means of X-ray analysis. In
the structures of the metal complexes, namely [Ag2(H2L)2](BF4)2·2H2O (1), [Ag(H2L)(NO3)]n (2), [Cu2(H2L)4(SO4)2]·11H2O (3), and {[Ag(H2L′)]BF4}n (4), the bipyrazoles act as bridging ligands to connect two metal atoms. Complexes 2 and 4 exhibit 1-D polymeric structures, while 1 and 3 are discrete molecules with a rectangular dimer or tetragonal prismatic shapes, respectively. Two different conformations,
namely cis and trans, have been observed for these bipyrazolyl ligands. 相似文献
10.
Prithwiraj Byabartta 《Transition Metal Chemistry》2005,30(7):804-813
Ag+ assisted aquation of blue cis-trans-cis-RuCl2(RaaiR′)2 (4–6) leads to the synthesis of solvento species, blue-violet cis-trans-cis-[Ru(OH2)2(RaaiR′)2](ClO4)2 [Raai R′=p-R-C6H4
N=N–C3H2–NN–1–R′, (1–3), abbreviated as N,N′-chelator, where N(imidazole) and N(azo) represent N and N′, respectively; R = H (a), OMe (b), NO2 (c) and R′ = Me (1/4/7/10), CH2CH3 (2/5/8/11), CH2Ph (3/6/9/12)] that have been reacted with NO2−in warm EtOH resulting in violet dinitro complexes of the type, Ru(NO2)2(RaaiR′)2 (7–9). The nitrite complexes are useful synthons of electrophilic nitrosyls, and on triturating the compounds, (7b–9b) with conc. HClO4 nitro-nitrosyl derivatives, [Ru(NO2)(NO)(OMeaaiR′)2](ClO4)2 (10b–12b) are isolated. The solution structure and stereoretentive transformation in each step have been established from 1H n.m.r. results. All the complexes exhibit strong MLCT transitions in the visible region. They are redox active and display
one metal-centred oxidation and successive ligand-based reductions. The redox potentials of Ru(III)/Ru(II) (E1/2M) of (10b–12b) are anodically shifted by ∼
∼0.2 V as compared to those of dinitro precursors, (7b–9b). The ν(NO) >1900 cm−1 strongly suggests the presence of linear Ru–NO bonding. The electrophilic behaviour of metal bound nitrosyl has been proved
in one case (12b) by reacting with a bicyclic ketone, camphor, containing an active methylene group and an arylhydrazone with an active methine
group, and the heteroleptic tris chelates thus formed have been characterised. 相似文献
11.
New mixed-ligand copper(I) complexes, [Cu(Phca2en)(PPh3)X], [Phca2en = N,N′-bis(β-phenylci-nnamaldehyde)-1,2-diiminoethane and X=Cl (1), Br (2), I (3), NCS (4), N3 (5)] have been synthesized and characterized by various techniques. 1H and 13C-NMR and IR spectral data of these copper(I) complexes are compared with the free ligand to elucidate some structural features. The structures of [Cu(Phca2en)(PPh3)Br] (2) and [Cu(Phca2en)(PPh3)I] (3) have been determined from single-crystal data showing that the coordination geometry around copper atom is a distorted tetrahedron. Furthermore, these Cu(I) complexes exhibit supramolecular motifs of the type multiple phenyl embraces resulting from attractive interactions between phenyl rings of PPh3 moieties. The presence of the C–H…Cu weak intramolecular hydrogen bonds, due to the trapping of C–H bonds in the vicinity of the metal atoms, is also reported. 相似文献
12.
Nucleophilic substitution of Pd(RaaiR′)Cl2 [(RaaiR′ = 1-alkyl-2-(arylazo)imidazole, p-R-C6H4-N=N-C3H2NN-1-R′; where R = H(a)/ Me(b)/ Cl(c) and R′ = Et(1)/Bz(2)] with 2-Mercaptopyridine (2-SH-Py) in acetonitrile (MeCN) at 298 K, to form [Pd2(2-S-Py)4], has been studied spectrophotometrically under pseudo-first-order conditions and the analyses support the nucleophilic association
path. The reaction follows the rate law, Rate = {k
0 + k [2-SH-Py]
0
2
}[Pd(RaaiR′)Cl2]: first order in Pd(RaaiR′)Cl2 and second order in 2-SH-Py. The rate of the reaction follows the order: Pd(RaaiEt)Cl2
(1) < Pd(RaaiBz)Cl2
(2) and Pd(MeaaiR′)Cl2 (b) < Pd(HaaiR′)Cl2 (a) < Pd(ClaaiR′)Cl2 (c). External addition of Cl− (LiCl) and HCl suppresses the rate (Rate ∝ 1/[Cl−]0 & ∝1/[HCl]0). The reactions have been studied at different temperatures (293–308 K) and activation parameters (Δ‡ H° and Δ ‡ S°) of the reactions were calculated from the Eyring plot and support the proposed mechanism. 相似文献
13.
[Ru(RaaiR)2(EtOH)2](ClO4)2[RaaiR= 1-alkyl-2-(arylazo)imidazole, p-R-C6H4-N = N-C3H2N-N(1)-R, R = H (a), Me (b), Cl (c), R= Me (1, 3), Et (2, 4)] reacts with nucleobases [NB – adenine (A), guanine (G)] in aqueous EtOH to give red–violet mixed ligand complexes of the type [Ru(RaaiR)2(NB)(H2O)](ClO4)2. The solution electronic spectra exhibit a strong MLCT band at 540–560 nm in MeCN. The cyclic voltammogram shows a RuIII/RuII couple at 1.3–1.4 V versus Ag/AgCl along with three successive ligand reductions. 相似文献
14.
P. Byabartta 《Russian Journal of Inorganic Chemistry》2009,54(9):1401-1406
The reaction of [Ru(OH2)2(RaaiR′)2]2+ (RaaiR′ = 1-alkyl-2-(arylazo)imidazole, p-R-C6H4-N=N-C3H2NN(1)-R′, R = H (1), Me (2), Cl (3); R′ = Me (a), Et (b), CH2Ph (c)) with 8-quinolinol (HQ) in acetone solution followed by the addition of NH4PF6 has afforded violet coloured mixed ligand complexes of the composition [Ru(Q)(RaaiR′)2](PF6). The maximum molecular peak of 1b is observed at m’z 790 (50%) in the ESI mass spectrum. Ir spectra of the complexes show
-C=N- and -N=N- stretching near at 1590 and 1370 cm−1. The 1H NMR spectral measurements suggest methylene, -CH2−, in RaaiEt gives a complex AB type while in RaaiCH2Ph it shows AB type quartets. Considering the arylazoimidazole and oxine moitie there are twenty different carbon atoms in
the molecule which gives a total of twenty different peaks in the C13 NMR spectrum of complex 1a. In the 1H-1H COSY spectrum of the present complexes, absence of any off-diagonal peaks extending from δ = 14.12 and 9.55 ppm confirm
their assignment of no proton on N(1) and N(3) respectively. Contour peaks in the 1H-13C HMQC spectrum in the present complexes, the absence of any contours at δ = 157.12, 160.76, 155.67 ppm and 157.68–160.2 ppm
assign them to the C(2), C(6), C(g) and C(h), C(i) carbon atoms respectively. The solution structure and stereoretentive transformation
in each step have been established from n.m.r. results. Cyclic voltammograme show a Ru(III)/Ru(II) couple at 1.0–1.1 V versus
SCE along with three successive ligand reductions. 相似文献
15.
《Journal of Coordination Chemistry》2012,65(16):2648-2655
Single crystals of Ag(I) and Cu(II) complexes with 4-pyridin-4-yl-(1,3) dithiol-2-one (PYDO), [Ag(PYDO)2]ClO4, [Ag(PYDO)2(NO3)], and [Cu(PYDO)2(NO3)2] have been prepared and characterized. PYDO displays excellent coordination to Cu(II) and Ag(I). The 1,3-dithiol five-member ring is an electron donor that enhances the coordination ability of the py group. HOMO-1 σ coordination and d–π electron back-donating from metal to ligand (LUMO) are suggested based on the calculation. Weak interactions and secondary bonds from the anion to cation play an important role in the molecular assembly. 相似文献
16.
Prithwiraj Byabartta 《Transition Metal Chemistry》2007,32(3):314-324
Silver assisted de-bromination gives [Au2(dppm/dppe/dppa) (OTf)2], which on reaction with 4,4′-bpy and gold(I) phosphines in CH2Cl2 medium, by the self assembly technique, leads to [(PPh3)Au(4,4′-bpy)Au(PPh3)], (1a–1d,2), [{Au2(dppm/dppe/dppa)}{(4,4-bpy)Au(PPh3)}2](NO3)4, (3), [{Au4(dppm/dppe/dppa)2(4,4-bpy)2}](OTf)4,
(4), [{(PPh3)AuI(4,4′-bpy)}2AuIII(C6F5/Mes)](NO3)3, (5) [dppm/dppe/dppa =diphenyl phosphino-methane(a), –ethane(b), ammine(c), C6F5/Mes pentafluorophenyl/mesitylene]. The maximum molecular peak of the corresponding molecule is observed in the ESI mass spectrum.
Ir spectra of the complexes show –C=C–, –C=N–, as well as phosphine, mesitylene and pentafluorophenyl stretching. The 1H-NMR spectra as well as 31P(1H)-NMR suggest solution stereochemistry, proton movement and phosphorus proton interaction. Considering all the moities there
are a lot of carbon atoms in the molecule reflected by the 13C(H)-NMR spectrum. In the 1H–1H COSY spectrum of the present complexes and contour peaks in the 1H–13C-HMQC spectrum, assign the solution structure and stereoretentive transformation in each step. 相似文献
17.
New mononuclear Fe (III), Cu (II), Ag (I), ZrO ( IV) and UO2(VI) complexes were synthesized by the reaction of metal ions with (E)-3-(2-(5, 6- diphenyl-1,2,4- triazin-3- yl)hydrazono)butan-2- one oxime. The structures of the metal complexes were characterized using analytical, spectral (infrared, electronic, 1H NMR, electron spin resonance (ESR), and mass), magnetic moment, molar conductance, thermal gravimetric analysis, and powder X-ray diffraction (XRD) measurements. All complexes have octahedral geometries except the Cu (II) complex, which has square planar geometry, and the UO2(VI) complex, in which the coordination number is seven. The ligand acts as a (neutral, monoanionic or dianionic) tridentate with N2O coordinating sites: N-azomethine, N-triazine, and O-oxime. Fluorescence spectral studies were carried out in solid state and in dimethylformamide (DMF). The kinetic parameters of the thermal decomposition stages were calculated using Coats–Redfern equations. The morphological structures of the ligand and some complexes were determined using XRD. The molecular orbital calculations were carried out for the ligand and metal complexes using the Hyperchem 7.52 program on the basis of the PM3 level. The antimicrobial activities of the ligand and its complexes were investigated towards the microorganisms S. aureus and B. subtilis as Gram-positive bacteria, S. typhimurium and E. coli as Gram-negative bacteria, C. albicans, and A. fumigatus. The ligand and its complexes showed antitumor activity against Hep G-2 cell lines, where Cu (II) and Ag (I) complexes seem to be promising as they showed IC50 values that are lower than and comparable to that of the antitumor drug doxorubicin. 相似文献
18.
Iron (II) complexes of 1-alkyl-2-(arylazo)imidazoles (p-R-C6H4-N=N-C3H2NN-1-R′, R = H (a), Me (b), Cl (c) and R′ = Me (1/3), Et (2/4) have been synthesized and formulated astris-chelates Fe(RaaiR′)
3
2+
. They are characterized by microanalytical, conductance, UV-Vis, IR, magnetic (polycrystalline state) data. The complexes
are low spin in character,t
2g
6
(Fe(II)) configurations. 相似文献
19.
Sushanta Saha Prodyut Kumar Sarkar Ambikesh Mahapatra 《Transition Metal Chemistry》2006,31(3):389-395
The reaction between Pd(N,N′)Cl2 [N,N′ ≡ 1-alkyl-2-(arylazo)imidazole (N,N′) and picolinic acid (picH) have been studied spectrophotometrically at λ = 463 nm in MeCN at 298 K. The product is [Pd(pic)2] which has been verified by the synthesis of the pure compound from Na2[PdCl4] and picH. The kinetics of the nucleophilic substitution reaction have been studied under pseudo-first-order conditions.
The reaction proceeds in a two-step-consecutive manner (A → B → C); each step follows first order kinetics with respect to
each complex and picH where the rate equations are: Rate 1 = {k′0 + k′2[picH]0} × [Pd(N,N′)Cl2] and Rate 2 = {k′′0 + k′′2[picH]0}[Pd(N,O)(monodentate N,N′)Cl2] such that the first step second order rate constant (k′2) is greater than the second step second order rate constant (k′′2). External addition of Cl− (as LiCl) suppresses the rate. Increase in π-acidity of the N,N′ ligand, increases the rate. The reaction has been studied
at different temperatures and the activation parameters (Δ‡H° and Δ‡S°) were calculated from the Eyring plot. 相似文献
20.
Dechlorination of Ru(PPh3)2(TaiMe)Cl2 (TaiMe = p-Me-C6H4-N=N-C3H2NN(1)-Me (1), 1-methyl-2-(p-tolylazo)imidazole) has been carried out in acetone solution by Ag+ and reacted with N,N’-chelators to synthesise [Ru(PPh3)2 (TaiMe)(N,N’)]2+. The complexes have been isolated as their perchlorate salts. The N,N’ chelators are 1-alkyl-2-(phenylazo)imidazoles (PaiX,
X = Me, Et, CH2Ph); 2-(arylazo)pyridines, (Raap,p-R-C6H4-N=N-C5H4N; R = H, Me, Cl); 2-(arylazo)pyrimidines (Raapm,p-R-C6H4-N=N-C3N2H2; R = H, Me, Cl); 2,2’-bipyridine (bpy) and 1,10-phenanthroline (o-phen). Unsymmetrical N,N’ chelators may give two isomers
and this is indeed observed. The1H NMR spectral data refer to the presence of two isomers in the mixture in different proportions. With consideration of coordination
pairs in the order of PPh3, PPh3; N,N (N refers to N(immidazole)) and N’,N (N’ refers to N(azo)), the complexes have been characterised astrans-cis-cis andtrans-trans-trans configuration; the former predominates in the mixture. Electrochemical studies exhibit high potential Ru(III)/Ru(II) couple
and quasireversible N=N reduction. Electronic spectra show high intensity (ε ∼ 104) MLCT transition in the visible region (520 ±10) nm along with a shoulder (ε ∼ 103) in the longer wavelength region. 相似文献