苯甲醛缩三乙烯四胺Schiff碱Co(Ⅱ)配合物固相合成及氧合性能研究

Three new cobalt complexes were synthesized by solid-state reaction at room temperature. It was found that one mole of complex reacted with two moles of oxygen at room temperature. And the oxygenated complexes [Co·(L₁)₂·2O₂](NO₃)₂·2H₂O (L₁=N,N′-bis(4-hydroxyl-3-methoxy-benzyl)-triethylenetetramine), [Co·(L₂)₂·2O₂](NO₃)₂ ·2H₂O (L₂=N,N′-bis(4-hydroxyl-benzyl)-triethylenetetramine) and [Co·L₃·2O₂](NO₃)₂·2H₂O (L₃=N,N′-bis(2-hydroxyl-benzyl)-triethylenetetramine) were obtained and characterized by elemental analysis, IR spectra, ¹H NMR, TG/DTA, UV-Vis and molar conductance. The coordinated oxygen contents in the oxygenated complex were also determined by weight method. It was found that one O₂ molecule coordinated to the Co ion and formed superoxo type oxygenated complex.     

Study on EPR Spectra of Three Gadolinium Complexes With Noncyclic Polyether Schiff Bases

The EPR spectra of three new gadolinium complexes with noncyclic polyether Schiff bases in powder and those of these complexes in organic solvents were investigated at different temperatures. It was observed that EPR spectra of nine and four peaks of Gd(Ⅲ) complexes in polycrystalline powder and freezing samples appeared at low temperature respectively for the first time. The interpretations of these results obtained on the basis of spin Hamiltonian of s = 7/2 system are satisfactory. The correlations of EPR feature between crystal-field strength in complexes and local symmetry around Gd3+ ions were revealed. The crystal-field parameters b20 and the asymmetry parameters λ' of complexes were estimated. A series of interesting regularity and new results were obtained.     

Schiff碱配合物模拟酶催化性能的温度效应研究

研究了新型Schiff碱双锰配合物在模拟酶催化亚碘酰苯单加氧化环已烷反应及 被亚碘酰苯氧化破坏反应中的温度效应。结果表明，在模拟酶催化反应体系中同时 存在催化环已烷单加氧反应及催化剂的氧化破坏反应；催化反应速率及氧化破坏反 应速率均随反应温度升高有规律地增大，但氧化破坏反应比催化反应对反应温度更 敏感；催化反应总产率一般随反应温度升高而降低；最适宜的反应温度为25 ℃。     

Synthesis,Crystal Structure,and Spectral Properties of a Cobalt(II) Complex with N‐Salicylidene‐p‐Toluidine

The complex Co(C₁₄H₁₃NO)₂Cl₂ with the protonated N‐salicylidene‐p‐toluidine ligand was synthesized from an ethanolic solution of CoCl₂·6H₂O and N‐salicylidene‐p‐toluidine. The crystal structure was determined from X‐ray single crystal data (monoclinic, space group Cc, a = 1496.2(3) pm, b = 1257.4(4) pm, c = 1544.6(3) pm, β = 115.01(1)°, Z = 4). Co²⁺ adopts a distorted tetrahedral geometry. The UV‐Vis and IR spectra of the complex are discussed.     

Über grünes Bis-(2-Iminoisopropyl-thiophenolato)-nickel(II) und weitere, ähnliche NiII-Komplexe

Green Bis-(2-iminoisopropyl-thiophenolato)nickel(II) and other Similar Ni^II Complexes The compounds [Ni^II(iitp)₂] 1 (iitp = 2-iminoisopropyl-thiophenolate), [Ni(imptp)₂] · 2 CH₃OH 2 , a dinuclear compound with an Ni? Ni distance of 276 pm, and [PPh₄] · [Ni^II(imptp)(SCN)] 3 (imptp = 2-(2-iminopentane-4-on)-thiophenolate) have been prepared by the reaction of nickel(II)-acetate-tetrahydrate with 2-iminoisopropyl-thiophenole and 2-(2-iminopentane-4-on)-thiophenole in methanol, respectively. They have been characterized by single-crystal X-ray structure analysis and other physical methods. The redox behaviour of 1–3 has been studied in detail (chemically as well as by cyclovoltammetry and ESR spectroscopy). Particularly interesting are the electronic properties of 1 and its reduction with NaBH₄ and the following reaction of the product with O₂. The complexes are model compounds for some Ni-containing enzymes. For details of the crystal structure determination see “Inhaltsübersicht”.     

All-trans-N-retinylidenetryptamine Schiff base in surfactant solubilized water pools in heptane—a fluorescence study

All-trns-N-retinylidenetryptamine Schiff base was incorporated into aerosol-OT (AOT, sodium bis(2-ethylhexyl)sulphosuccinate)/heptane reverse micelles. This micellar system was used as a model to study the retinal-tryptophan interactions in retinal proteins. The retinylidene Schiff base remains stable in the presence of reverse micelle-solubilized water pools. Partition coefficient and microviscosity measurements show that the Schiff base is located in the micellar interphase. The results are discussed in terms of the interaction between the retinylidene chromophore and the active site environment of rhodopsin and bacteriorhodopsin. In the present model, the quencher and emitting units are covalently attached, and are separated by two carbon spacer units. The fluorescence emission data obtained for the micelle-intercalated Schiff base chromophore are compared with the fluorescence of the native protein and intermediates in the photochemical cycle of bacteriofhodopsin. A comparison of the data obtained for tryptamine and the Schiff base with the results available for bacteriorhodopsin and bacterioopsin reveals that there is a large degree of quenching on intercalation of the retinylidene chromophore in the vicinity of the fluorophore. Evidence provided by this model suggests that energy transfer to retinal can occur from tryptophan residues located in the retinal pocket in the native protein. Thus the retinylidene unit can act as a quencher of the energy of tryptophan, the nature and extent of which may depend on the conformation and relative orientation of the protein-bound fluorophore.     

Chiral base route to functionalised cyclopentenyl amines: formal synthesis of the cyclopentene core of nucleoside Q

A chiral base route to a range of highly functionalised amino cyclopentenes has been developed. The key asymmetric step involved the chiral lithium amide base-mediated rearrangement of a protected trans-4-hydroxy cyclopentene oxide to give an allylic alcohol (88% ee). Subsequent Overman rearrangement gave a protected trans-1,2-aminocyclopentenol whereas Mitsunobu substitution with BocNHNs gave a protected cis-amino cyclopentenol. Both are proven intermediates for natural product synthesis. The protected cis-aminocyclopentenol was transformed in a few steps into a precursor of the cyclopentene core of nucleoside Q, a natural product whose deficiency in animals is related to tumour growth.     

异亚硝基乙酰乙酸乙酯亚胺Pd(Ⅱ)配合物的合成、表征和tran Pd(p-CH3C6H4-IEAI)2的晶体结构

Six palladium(Ⅱ) complexes with isonitrosoethylacetoacetate imine Schiff base ligands, Pd(R-IEAI)₂, were prepared and characterized by IR, Raman and electronic spectra. Complex tran Pd(p-CH₃C₆H₄-IEAI)₂ (2) cry- stallizes in the monoclinic system, space group P2₁/c,with a=1.2002(2),b=0.9972(2),c=1.1121(2)nm,β=90.43(3)°,Z=2,F(000)=616,μ=7.44cm^-1. The final R and wR are 0.0244 and 0.0625 for 2620 ob-served reflections with I≥2σ(I), respectively. The geometry around the Pd(Ⅱ) ions in those complexes has a distorted PdN₄ square plane, the Schiff base ligands R-IEAI^- being coordinated through their oximino-nitrogen atoms and imino-nitrogen atoms.     

Synthesis and magnetic properties of poly(p‐phthaloyl‐disacetylaceton‐ethylenediimine) metal complexes

Macrocyclic Schiff‐base ligand, bisacetylaceton‐ethylenediimine (BAE) and its transition metal complexes M(BAE) (M = Cu²⁺, Ni²⁺) were synthesized. The complexes having characteristics of aromatic systems and well‐defined one‐dimensional structures, reacted with p‐phthaloyl chloride, to obtain polymer complexes. The complexes were characterized by elemental analysis, inductively coupled plasma (ICP), FT‐IR, and thermal analysis and show good thermal stability. ESR spectra analysis discovered that there are free radicals in the chain of polymers, indicating that a weak magnetic spin‐exchange interaction operates between the metal ions and free radicals. It is found that, as the bridging p‐phthaloyl group is able to propagate the magnetic exchange interaction, the polymer complexes show paramagnetic properties by measurement of temperature dependence of the magnetic property, and obey Curie–Weiss law. Copyright © 2001 John Wiley & Sons, Ltd.