TERNARY COPPER(Ⅱ) -HISTIDINE-NUCLEOTIDE COMPLEXES

The ternary copper(Ⅱ)-histidine-nucleotide complexes with purine (5″-AMP, 5″-GMP, 5′-IMP) nucleotides were prepared and characterized by elemental analyses, conductivity measurements, IR and ~1H NMR spectra.     

SYNTHESIS AND MAGNETISM OF BINUCLEAR COPPER(Ⅱ) COMPLEXES CONTAINING SALUCYLAMIDATOCUPRATE(Ⅱ)

New binuclear copper(Ⅱ) complexes, [Cu(samen)Cu(NO_2-phen)]·H_2O and [Cu(sampn)-Cu(NO_2-phen)]·2H_2O have been synthesized, where samen~(4-), sampn~(4-) and NO_2-phen denote N, N′-ethylenedisalicylamidate anion, N, N′-1, 2-propanedisalicylamidate anion and 5-nitro-1, 10-phenanthroline respectively. 3ased on IR, elemental analyses and electronic spectra, the complexes are proposed to have a phenoxy-bridged structure and to consist of the Cu(Ⅱ)ion in distorted planar environment. The complexes have been characterized with varlable-temperature magnetic susceptibility (4—300 K) and the observed data were fit to those from a modified Bleaney-Bowers equation by least-squares method, giving the exchange integral J=-63.0 cm~(-1) (samen) and J=-46.5cm~(-1) (sampn). This indicates the existence of antiferromagnetic spin exchange interaction among the metal ions.     

SYNTHESIS AND ELECTRONIC SPECTRA OF RUTNENIUM(Ⅱ)-1,1''''-BIISOQUINOLINE COMPLEXES

l,l'-biisoquinoline can coordinate with ruthenfum(Ⅱ) to form a new series of mononuclear complexes and the electronic absorption of these complexes were measured and reasonably assigned.     

THE ESR STUDY OF SOME DICYCLOPENTA-DIENYL TITANIUM HALIDE COMPLEXES

The ESR spectra of some [Cp_2Ti(L)X] complexes (Cp: C_5H_5, MeC_5H_4; L: phosphane,isocyanide, pyridine, amine and carbon monoxide; X: F, Cl, Br, I) have been obtained.When X is Cl, Br or I, the linear relationships between the g value and hyperfine couplingcoustant a(Ti) are explained in terms of the electron character of the L ligand and the ESRspectral trends of the complexes are studied.     

ESR SPECTRA OF VO(NCS)_n~((2-n) ) COMPLEXES AND DETERMINATION OF THEIR STABILITY CONSTANTS

The ESR spectra of VO(NCS)_n~((2-n) ) complexes have been studied in this paper. It is shown that four complexes ions of various compositions, VO(NCS)~ , VO(NCS)_2, VO(NCS)_3~- and VO(NCS)_4~(2-), are formed in glyeol-water-mixed media. The parameters of the ESR spectra have been determined. We established a linear correlation between the hyperfine coupling constant and the coordination number n. n=117.66-3.41n (gauss). All the stability constants for various complexes formulated as VO(NCS)_n~((2-n) )(n=1,2,3,4) have been calculated from the ESR spectra, log K_1=2.15; log K_2=1.55; log K_3=0.87; log K_4=0.22. K_3and K_4 have not been reported in literature up to now.     

PREPARATIONS OF COPPER (Ⅰ) COMPLEXES WITH NOVEL PYRAZOLYLBORATES

ＰＲＥＰＡＲＡＴＩＯＮＳ　ＯＦ　ＣＯＰＰＥＲ（Ⅰ）ＣＯＭＰＬＥＸＥＳ　ＷＩＴＨ　ＮＯＶＥＬ　ＰＹＲＡＺＯＬＹＬＢＯＲＡＴＥＳＰＲＥＰＡＲＡＴＩＯＮＳＯＦＣＯＰＰＥＲ（Ⅰ）ＣＯＭＰＬＥＸＥＳＷＩＴＨＮＯＶＥＬＰＹＲＡＺＯＬＹＬＢＯＲＡＴＥＳ￥ＫｅＷｕＹ...     

SYNTHESIS, STRUCTURE AND MAGNETISM OF μ-OXAMIDO BINUCLEAR COPPER(Ⅱ) COMPLEXES

Two new binuclear copper(Ⅱ) complexes, [Cu(oxpn)CuL](ClO_4)_2, have been synthesizedand characterized, where oxpn is N,N' bis(3-aminopropyl)oxamido and L is 1,10-phenan-throline (phen) or 5-nitro-1,10-phenanthroline (NO_2-phen). The crystal structure and vari-able-temperature magnetic susceptibility (4- 300 K) of the Complex (L=phen) have beendetermined. Crystal data: orthorhombic system, space group Pnma, with a = 10.433(1), b11.458(2), c = 21.999(2)A, z = 4. Every copper(Ⅱ) ion is in a square pyramidal environment.The two copper(Ⅱ) ions are linked by μ-oxamido bridge and the separation of them is 5.208A. The singlet-triplet energy gap J was found equal to -452.92cm~(-1), indicating that astrongantiferromagnetic spin-exchange interaction operates between the copper(Ⅱ) ions.     

STUDY ON THE KINETICS OF POLYMERIZATION OF MMA BY COPPER (Ⅱ) CHELATING RESINS

The polymerization of MMA initiated by copper (Ⅱ) chelating resins/CCl4 system was studied. From the kinetic data, the kinetic equation of polymerization can be expressed asRp = Ke-56400/RT[MMA]1.57[CCl4]m[RESIN-Cu]0.18where m:3-4. 5,when [CCl4] 0. 1-6. 93M. The free radical polymerization mechanism is proposed. The primary radicals are formed by the process of complexation-chlorine transformation among the copper(Ⅱ)chelating resin,CCl4 and methacrylate.     

HYDRAZONES CONTAINING NORBORNENYL AND THEIR COPPER(Ⅱ) COMPLEXES

ＨＹＤＲＡＺＯＮＥＳＣＯＮＴＡＩＮＩＮＧＮＯＲＢＯＲＮＥＮＹＬＡＮＤＴＨＥＩＲＣＯＰＰＥＲ（Ⅱ）ＣＯＭＰＬＥＸＥＳ￥ＱｉｎｇＢａｏＳＯＮＧ；ＸｉａｏＬｉＷＵ；ＭｉｎｇＴｉａｎＬＩａｎｄＹｏｎｇＸｉａｎｇＭＡ（ＤｅｐａｒｔｍｅｎｔｏｆＣｈｅｍｉｓｔｒｙ...     

ESR SPECTHOSCOPIC STUDY OF ACETONITRILE-Cu(Ⅱ) COMPLEX ON Y-TYPE ZEOLITE

<正> Acetonitrile-Cu(II) complex on Y-type zeolite was studied by ESR and the electronic structural parameters of the complex were calculated.The results are reported here and the bonding properties between the transition metal ion and the ligand, as well as their energy relationships are discussed.     

A STUDY OF DOUBLY CHARGED ION MASS SPECTRA(2E SPECTRA) OF BIPHENYL DERIVATIVES

The 2E spectra and substituent effects and target gas pressure dependence of the 2E spectra of 7 biphenyl derivatives were discussed. The electron-donating groups favour the molecular ions, but the electron withdrawing groups favour the fragaent ions produced by losing the substituents from molecular ions. The variation of target gas pressure affects the TIC,sample ion current,and the ratio of sample ion current to TIC sharply.However it has no effect on the fragmentation pattern.     

STUDY ON ESR SPECTRUM OF BIS(2-HYDROXYL-PHENYLKETOXIME)-COPPER (Ⅱ) COMPLEX

A better resolution of ESR spectrum of bis(2-hydroxyl-phenylketoxime)copper (Ⅱ) complex intetrahydrofuran (THF) solution, measured at liquid nitrogen temperature, was analyzed. From thespectrum, we have not only got hyperfine splitting of the ~(63)Cu and ~(65)Cu, but also very nice super-hyperfine splitting arising from ~(14)N nucleus. The g_x, g_y, g_z; A_x~(63), A_y~(63), A_z~(63); A_x~(65), A_y~(65), A_z~(65); A_∥~N andA_⊥~N etc. tensor parameters were determined rather reasonably. From these, we calculated the bondingparameters of this complex, and discussed its electronic structure.     

STUDY ON THE STRUCTURES OF COORDINATION COMPOUNDS OF N-(ortho-METHYL)-AND N-(ortho-METHOXY)-PHENYL IMINODIACETATO-Cu(Ⅱ)

The coordination compounds,{Cu[CH_3C_6H_4N(CH_2COO)_2]}.2H_2O and{Cu[CH_3OC_6H_4N(CH_2COO)_2]}.2H_2O,have been prepared and its crystal struc-tures determined.The final discrepancy factors are R=0.052,R_w=0.061 for(I)and R=0.052,R_w=0.039 for(Ⅱ).The geometry of the coordination poly-hedron with Cu(Ⅱ)is a distorted tetragonal pyramid for(Ⅰ)and an unsym-metrical and extended tetragonal bipyramid for(Ⅱ),respectively.The re-sults of EHMO calculations indicate that the ligand mainly provided thefield with very few of its electrons being coordinated to the central atom.     

SYNTHESIS AND STRUCTURE OF Cu(Ⅱ)COMPLEXES BY OXIDATIVE ADDITION OF DIBENZOYL PEROXIDE ON METALLIC COPPER

Dibenzoyl peroxide undergoes oxidative addition on metallic copperpowder with 2,2′-bipyridine(or imidazole)in a mixed solvent(methanol andtetrahydrofuran),and affords the Cu(Ⅱ)complexes-[Cu(Ce(C_6H_5COO)_2(2,2'-bipy)]H_2O(1)and[Cu(C_6H_5COO)_2(C_3H_4N_2)_2](2).The structure was solved by direct methodsand Fourier synthesis.C_(24)H_(20)N_2O_5Cu (1),Mr=479.78,space group P2(1)/c,a=6.986(7),b=18.833(I),c=17.021(3),α=γ=90°,Z=4,V=2218.1~3,Dc=1.443g/cm\+3,R=0.055Rw=0.062.Complex(2),C_(20)H_(18)N_4O_4Cu(2),Mr=441.74,space group P2(1)/n,a=8.699(4),b=9.840(6),c=12.399(5),α=γ=90°,β=100.8°,Z=4,V=1010.9~3,Dc=1.654g/cm\+3,R=0.055,Rw=0.062.     

TIME RESOLVED SPECTRA OF Eu(MBA)_3 PHEN COMPLEXES

Time-resolved fluorescence spectra of europium methylbenzoates(MBA)with 1,10-phenanthroline(phen)have been measured at room temperature.Foreach of the europium chelates,where the ligand triple states lie above the ~5D_1 level ofEu~(3-),the spectra providc evidence that the Eu~(3-) ~5D_0 state is populated by nonradiativeenergy transfer from the higher-lying ~5D_1,state.The relaxation time for energy decayfrom ~5D_1 state is measured in the microcrystals to bc of the order of a fewmicroseconds.It is suggested that the ligand C=0 and C=C stretching vibrations andEu-O vibrations,chclate ring and benzene ring vibrations make importantcontributions to the relaxation process.The ~5D\-1—~5D\-0 relaxation time of Eu-(p-MBA)_3phen is shorter than those of Eu(m-MBA)_3phen and Eu(o-MBA)_3phensince nonradiative degradation to ~5D_0 from ~5D_1 appears to be more strongly influencedby the E_u~(3+)sites in the former.     

COORDINATION POLYMERIZATION OF BENZOTRIAZOLE ON THE SURFACE OF METALLIC COPPER

The coordination polymerization of benzotriazole with metallic copper has been investigated by infrared and X-ray photoelectron spectroscopies. We found that benzotriazole could react with copper (0) under mild conditions to form bis (benzotriazolato) copper (Ⅱ) and benzotriazolato copper (Ⅰ)which covered the surface of copper metal in the shape of polymeric materials. Since benzotriazole is of great interest as a ligand in that its presence in many biological system with metal ions, and is considered as a corrosion inhibitor, this work will be in favour of the study of protective corrosion.     

EFFECTS OF CONFORMATION OF POLYMER LIGANDS IN COPPER(Ⅱ) COMPLEXES ON CATALYLIC ACTIVITIES AND MECHANISM OF OXIDATIVE COUPLING OF β-NAPHTHOL

Copper(Ⅱ) complexes of sericin, chitosan, 6-and 2-aminodeoxystarch were used as catalysts in oxidative coupling of β-naphthol, the effects of conformation of the polymer ligands in these complexes on activities of the catalysts and mechanisms of the reaction were studied. It was found that if the catalysts react with the substrate by mechanism similar to the enzymic catalysis they must be composed of polymer ligands with highly coiled, especially with densely helicoidal, conformations. While catalysts composed of loosely coiled or helicoidal hgands react with the substrate through molecular collision and have relatively lower activities only. Under nitrogen, catalysts from sericin and chitosam reacting with β-naphthol give optically active β-binaphthol, rotating polarized light to right, but the stereoselectivities are rather low.     

THE MOSSBAUER SPECTRA AND COORDINATION STRUCTURE OF TRICYCLOHEXYLTIN CARBOXYLATES

<正> The Mossbauer spectra and IR spectra of a series of new tricyclo-hexyltin carboxylates, (C5H11)3SnOCOR, showed that there was only four-coordinate tin in each compound and no intermolecular oxygen to tin coordination for the bulkiness of cyclohexyls and R groups.     

SELENOETHER COMPLEXES OF COPPER(II) ‐ SYNTHESIS,SPECTROSCOPY AND STRUCTURES

Abstract

The red-brown copper(II) diselenoether complexes, [Cu (L-L)₂][BF₄]₂ (L-L = MeSeCH₂CH₂SeMe, MeSeCH₂CH₂CH₂SeMe or PhSeCH₂CH₂SePh) have been prepared from copper(II) fluoroborate and the ligands in anhydrous dichloromethane. Some new dithioether analogues are also described. The reaction of MeSeCH₂CH₂SeMe and copper(II) fluoroborate in ethanol led to an unstable dark green substance which appeared to contain both copper(I) and copper(II) and was formulated [Cu(MeSeCH₂CH₂SeMe)₂] [BF₄]_x. The complexes were characterised by analysis, UV-visible and e.p.r. spectroscopy, and magnetic measurements, and cyclic voltammetry has been used to probe the Cu (II)/Cu(I) redox couples. The complexes are too unstable in solution to obtain crystals for an X-ray study, but structural data has been obtained for both the Cu(II) and Cu(I) complexes by copper K-edge EXAFS studies. Ditelluroethers reduce copper(II) salts to copper(I) complexes.     

SPECTROSCOPIC and REDOX BEHAVIOUR OF SOME COPPER(II) ‐ THIOETHER COMPLEXES

Abstract

The features of electronic spectra and redox chemistry of a number of Cu(II)-thioether complexes have been examined. The origin of the intense absorption in the region around 14,000–16,000 cm^?1 is attributed to (π)S → d(Cu²⁺) CTB, that obscures the less intense d-d (Cu²⁺) band. The relationship between spectral characteristics and redox potentials of CuL^2+/+ couples values is discussed.