二聚体[Ni(TSSB)(Phen)(H_2O)]·4H_2O的合成、表征、晶体结构及热分解研究

0引言含硫席夫碱及其金属配合物具有抑菌、抗癌和抗病毒的生物活性[1￣3],有些含O、N席夫碱金属配合物具有仿酶催化活性[4,5]。而氨基酸席夫碱配合物具有良好的生物生理活性,近年来得到人们的普遍重视[6,7],同α-氨基酸席夫碱相比,β-氨基酸席夫碱由于氨基位置的变化而引起不同     

SpinPHOX/Ir(Ⅰ)催化的2-羟甲基-3-芳基丙烯酸的不对称氢化

光学活性的2-羟甲基-3-芳基丙酸类化合物是许多手性药物的关键合成中间体,但到目前为止其不对称合成方法大多存在对映选择性不高及/或底物范围有限等问题.报道了手性SpinPHOX/Ir(I)络合物在一系列2-羟甲基-3-芳基丙烯酸的不对称氢化中表现出优良的催化性能,取得完全的底物转化和良好到优秀的对映选择性(高达95%ee).对于同一2-羟甲基-3-芳基丙烯酸底物的不对称氢化,使用中心手性相同但螺环骨架上的轴手性相反的催化剂分别以优良的对映选择性获得构型相反的产物,从而为光学活性2-羟甲基-3-芳基丙酸及相关手性药物的不对称合成提供了一条简便高效的途径.     

手性三元铜(Ⅱ)配合物的制备及其在菊酸不对称合成中的应用

手性金属配合物催化剂在不对称合成中占有重要地位^[1-3]。在该类催化剂参与的不对称催化反应中,配合物中手性配体是催化反应立体选择性优劣的关键^[4,5]。为了改进该类催化剂的性能,主要对手性配体进行过化学修饰。目前合成的手性催化剂几乎都是由同一种手性配体和一种金属离子组成的二元配合物,且高效者并不多.文献[6]曾提到有关手性三元配合物(亦称手性混合配体配合物)。在不对称催化中应用的可能性,但未见具体报道。本文以中性含氮配体和含氧酸与铜(Ⅱ)配位合成了一类手性三元铜(Ⅱ)配合物及其在不对称合成菊酸中的催化性能。     

牛磺酸缩3,5-二溴水杨醛席夫碱镁配合物[Mg(Br_2TSSB)(Phen)(H_2O)]·H_2O的合成及晶体结构

0引言含硫席夫碱及其金属配合物具有抑菌、抗癌和抗病毒的生物活性[1￣3],有些含O、N席夫碱金属配合物具有仿酶催化活性[4,5]。而氨基酸席夫碱配合物具有良好的生物生理活性,近年来得到人们的普遍重视[6,7]。同α-氨基酸席夫碱相比,β-氨基酸席夫碱由于氨基位置的变化而引起不同的配位特征,但研究此类席夫碱的报道目前还不多[8￣10]。2-氨基乙磺酸(牛磺酸)作为生物体内一种特殊的氨基酸,目前对它的研究主要集中在生理和病理方面,它的席夫碱及其配合物的研究或牛磺酸金属配合物的研究刚起步[2,10￣17]。研究表明,-SO32-可以与碱金属、碱土…     

配合物[Co(benimtacn)Cl2]Cl·3H2O的合成、晶体结构及电化学性质

近年来,带悬臂的1,4,7-三氮环壬烷作为一类直接有效的配体引起了人们的兴趣[1,2],由于悬臂的柔顺性和多样性,这类配体可能形成非常有趣且稳定的配合物[3￣5]。特别是选择性悬臂配体形成的配合物,作为酶模型物时,容易形成催化活性空位[6￣8];悬臂较少,空间位阻较小的配体在形成配合物时易自组装成桥连双核二聚体[9,10]。     

新手性配体(QN)2AQN的合成及其催化肉桂酸甲酯的不对称氨羟化反应研究

在AlCl₃和多聚磷酸的存在下, 以邻苯二甲酸酐和对二氟苯为原料, 通过Friedel-Crafts和环化反应, 用改进的方法以60%的产率生成1,4-二氟蒽醌. 然后通过奎宁锂与1,4-二氟蒽醌的亲核取代反应得到新型手性配体(QN)₂AQN, 产率85%. 在氧化-供氮试剂N-氯代氨基甲酸苄酯存在下, (QN)₂AQN与OsO₄原位生成的催化剂在五种肉桂酸甲酯的不对称氨羟化反应中表现出优异的对映选择性(90%～96% ee)和一般至优秀的区域选择性(75∶25～98∶2), 产率50%～70%, 高于文献报道的结果. 该手性配体易于合成, 成本低廉, 用于催化不对称氨羟化反应, 可以制备光学活性的α-氨基酸酯类化合物.     

(1S,2S)-DPEN修饰的Ir/Al2O3催化苯乙酮及其衍生物的不对称加氢反应$

在碱性条件下制备了三氧化二铝负载的铱(Ir/γ-Al2O3)催化剂,并用于苯乙酮及其衍生物的不对称催化加氢反应.考察了不同的碱、碱浓度、手性二胺(1S,2S)-1,2-二苯基乙二胺[(1S,2S)-DPEN]浓度、反应温度和反应压力对催化剂及反应的影响.结果显示,在优化反应条件下,该催化剂表现出较高的催化活性和良好的对映选择性,其中异丁酰苯不对称催化加氢反应的对映选择性达到了80.3%.该催化剂不需要使用任何稳定剂,制备方法简单,催化性能稳定,通过简单的离心分离即可循环使用.     

新型手性膦-硼烷配合物的合成及其在不对称催化氢化反应中的应用

以苯乙烯为原料,通过Sharpless不对称二羟基化反应合成高对映体纯的苯基乙二醇,经酯化、亲核取代反应转化为手性膦-硼烷配合物.后者克服了有机膦配体易氧化的缺点,其制备过程简单,易于提纯,在空气中可长期保存.该手性膦-硼烷配合物在四氟硼酸-甲醚的存在下解络,生成的自由膦不经分离直接与[Rh(COD)Cl]₂作用生成手性膦-铑原位催化剂.在α-乙酰氨基肉桂酸甲酯的不对称氢化反应中,转化率为100%,对映选择性88%e.e.     

手性β-氨基醇催化α,β-不饱和酮的不对称环氧化反应

将以烯烃为原料通过Sharpless不对称双羟化等多步反应合成的8种手性β-氨基醇, 作为有机小分子催化剂, 用于催化α,β-不饱和酮的不对称环氧化反应．考察了影响对映选择性的催化剂结构、催化剂用量、氧化剂种类、溶剂、反应温度等因素．结果表明, 当催化剂用量为30 mol%、氧化剂为TBHP(叔丁基过氧化氢)、正己烷溶剂、在室温下、以(1S,2R)-(＋)-1,2-二苯基-2-甲氨基乙醇(3)作催化剂时, 所得环氧化物的对映体过量最高为70% ee, 产率最高为84%.     

手性Schiff Base-Ti(OR)4配合物催化醛的不对称硅腈化反应

设计合成了新型手性Salen-Ti(OR)₄配合物催化剂,用其催化一系列醛的不对称硅腈化反应,得到了e.e.值为22.4%～87.1%的氰醇.催化剂中抗衡离子的Lewis碱强烈地影响催化活性,但对反应的对映选择性影响很小,并探讨了其不对称催化反应机理.     

不对称Salen配体的Ni(Ⅱ)/Cu(Ⅱ)/Mn(Ⅲ)配合物的合成及其晶体结构

将(1R,2R)-环己二胺与2-羟基-1-萘甲醛和3,5-二叔丁基水杨醛反应,得到非对称Salen配体H2L,然后将配体H2L与Ni(OAc)2·4H2O、Cu(OAc)2·H2O、Mn(OAc)2·4H2O进行配位反应,得到3个单核配合物[Ni(L)]·CH2Cl2(1),[Cu(L)](2),[Mn(L)(Cl)]·CH2Cl2(3),分别采用1H NMR、FT-IR和元素分析对化合物进行了表征,并通过X射线单晶衍射技术测定了配体和3个配合物的晶体结构。配体H2L属于正交晶系,P212121空间群。配合物1属于单斜晶系,P21/c空间群,而配合物2和配合物1的结构相似。配合物3属于三斜晶系,P1空间群。     

(1iR, 1iiR, 2iR, 2iiR)-Ni, Nii-(1,3-亚苯基双(亚甲基))环己烷-1,2-二胺作为配体的双核铂配合物的合成及其抗癌活性

以(1ⁱR,1ⁱⁱR,2ⁱR,2ⁱⁱR)-Nⁱ, Nⁱⁱ-(1,3-亚苯基双(亚甲基))环己烷-1,2-二胺(HL)作为配体,设计并合成了7种双核铂配合物,并利用IR,¹H NMR,¹³C NMR,ESI-MS和元素分析等进行了表征。通过MTT法测定目标双核铂配合物对人类HepG-2,A549,HCT-116和MCF-7四种癌细胞系的细胞毒性。结果表明,所有的化合物对HepG-2,A549和HCT-116细胞系均表现了良好的细胞毒活性,但对MCF-7细胞系均无活性。其中,以3-羟基环丁烷-1,1-二羧酸为离去基团的配合物P7对HepG-2和A549细胞系的活性优于卡铂,对HCT-116细胞系的活性接近于奥沙利铂。     

Synthesis,structure, and solvent-extraction properties of tridentate oxime ligands and their cobalt(II), nickel(II), copper(II), zinc(II) complexes

Synthesis of four different types of ligands Ar[COC(NOH)R] _n (Ar = biphenyl, n = 1, HL¹; Ar = biphenyl, n = 2, H₂L²; Ar = diphenylmethane, n = 1, HL³; Ar = diphenylmethane, n = 2, H₂L⁴; R = furfurylamine in all ligands) and their dinuclear Co²⁺, Ni²⁺, Cu²⁺, and Zn²⁺ complexes is reported herein. These compounds were characterized by elemental analysis, ICP-OES, FT-IR spectra, and magnetic susceptibility measurements. The ligands were further characterized by ¹H NMR. The results suggest that dinuclear complexes of HL¹ and HL³ have a metal to ligand mole ratio of 2: 2 and dinuclear complexes H₂L² and H₂L⁴ have a metal to ligand mole ratio of 2: 1. Square pyramidal or octahedral structures are proposed for complexes of oxime ligands. Furthermore, extraction abilities of the four ligands were also evaluated in chloroform using selected transition metal picrates such as Mn²⁺, Co²⁺, Ni²⁺, Cu²⁺, Zn²⁺, Cd²⁺, Hg²⁺, Pb²⁺. The ligands show strong binding ability towards Hg²⁺ and Cu²⁺ ions.     

STEREOCHEMISTRY OF (R)-2-METHYLAZIRIDINE COMPLEXES OF COBALT(III) AND DIMERIZATION OF THE LIGAND

Abstract

A cobalt(III) complex containing (R)-2-methylaziridine (R-meaz), [Co(R-meaz)(NH₃)₅]³⁺, was prepared and the two diastereomers arising from the presence of the chiral nitrogen atom (N(R) and N(S)) were separated by column chromatography. Molecular mechanics calculations estimated the N(R)-isomer to be more stable. This result was supported by the x-ray structure determination of the more abundant (ca. 94%) isomer, N(R)-[Co(R-meaz)(NH₃)₅]Br₃H₂O. Crystal data: monoclinic, P2₁, a = 7.357(1), b = 9.780(1), c = 10.426(1) Å, μ = 93.58(1)°, V= 748.7(3) ų, Z= 2. Kinetic studies of isomerization (epimerization) between the two isomers revealed that inversion at the nitrogen center was very slow (5 × 10^?2 M^?1 S^?1at 25 °C). The small rate constant seems to be related to the strained three-membered structure of the meaz ligand. The reaction of Na₃[Co(N0₂)6] and R-meaz yielded a complex containing two dimerized R-meaz chelates, trans-[Co(NO₂)2(di-R-meaz)₂] (di-R-meaz =RR)-α,2-dimethyl-l-aziridineethanamine). The crystal strucrure of trans-[Co(NO₂)₂ (di-R-meaz)₂]C1O₄H₂O was established by x-ray crystallography. Crystal data: orthorhombic, P2₁2₁2₁, a = 11.784(6), b = 21.023(9), c = 8.608(7) Å, V = 2133(2) ų, Z = 4.     

(1iR,1iiR,2iR,2iiR)-Ni,Nii-(1,3-亚苯基双(亚甲基))环己烷-1,2-二胺作为配体的双核铂配合物的合成及其抗癌活性

以(1ⁱR,1ⁱⁱR,2ⁱR,2ⁱⁱR)-Nⁱ,Nⁱⁱ-(1,3-亚苯基双(亚甲基))环己烷-1,2-二胺(HL)作为配体,设计并合成了7种双核铂配合物,并利用IR,¹H NMR,¹³C NMR,ESI-MS和元素分析等进行了表征。通过MTT法测定目标双核铂配合物对人类HepG-2,A549,HCT-116和MCF-7四种癌细胞系的细胞毒性。结果表明,所有的化合物对HepG-2,A549和HCT-116细胞系均表现了良好的细胞毒活性,但对MCF-7细胞系均无活性。其中,以3-羟基环丁烷-1,1-二羧酸为离去基团的配合物P7对HepG-2和A549细胞系的活性优于卡铂,对HCT-116细胞系的活性接近于奥沙利铂。     

Synthesis and in vitro cytotoxicity of novel dinuclear platinum(II) complexes containing a chiral tetradentate ligand

A series of novel dinuclear platinum(II) complexes with a chiral tetradentate ligand, (1R,1′R,2R,2′R)-N¹,N¹′-(1,2-phenylenebis(methylene))dicyclohexane-1,2-diamine (HL), and mono-carboxylic acid derivatives as ligands have been designed, synthesized, and characterized. In vitro cytotoxicity evaluation of synthesized complexes against human HepG-2, A549, HCT-116, and MCF-7 cancer cell lines has been conducted by MTT assays. All compounds showed antitumor activity to HepG-2 and HCT-116 cell lines. Compound L2 exhibited better cytotoxicity than that of carboplatin against HepG-2 and A549 cell lines and also showed comparable activity against HCT-116 cell line.     

Chromium(III), manganese(II), iron(III), cobalt(II), nickel(II) and copper(II) complexes with a pentadentate, 15-membered new macrocyclic ligand

Complexes of Cr^III, Mn^II, Fe^III, Co^II, Ni^II and Cu^II containing a macrocyclic pentadentate nitrogen–sulphur donor ligand have been prepared via reaction of a pentadentate ligand (N₃S₂) with transition metal ions. The N₃S₂ ligand was prepared by [1 + 1] condensation of 2,6-diacetylpyridine with 1,2-di(o-aminophenylthio(ethane. The structures of the complexes have been elucidated by elemental analyses, molar conductance, magnetic susceptibility measurements, i.r., electronic and e.p.r. spectral studies. The complexes are of the high spin type and are six-coordinate.     

Solution Structure and Behavior of Benzophenone-based Achiral Bisphosphine Ligands in Noyori-Type Ru（Ⅱ）-Catalysts

We herein report on solution structural studies of Ru^Ⅱ catalysts （3a, 9） composed of achiral bisphosphine ligands （4, 8） and the enantiopure 1,2-diphenylethylenediamine （DPEN）. Complete chiral induction from enantiopure （R,R）-DPEN to achiral bisphosphine ligand 3a was observed in solution, with the complex adopting a single, stable and non-fluxional （even at 70 ℃） configuration. The coordination of the C=O moiety in 4 to the cationic Run center is considered to be of key importance in providing the higher thermodynamic and kinetic rotation barrier for the flexible bisphosphine ligand in the complex. The obtained enantioselectivity （91% enantiomeric excess） and sense of chiral induction in the hydrogenation of acetophenone were found to be solely dependent on the chirality of the 1,2-diamine. Consistent with the hydrogenation product, the （R,R）-DPEN induces a M-conformation （fight-handed） chirality for flexible phosphine ligand 4 in the complex, resulting in a 2,2-configuration about the Ru^Ⅱ center.     

Synthesis,structures, and property studies on Zn(II), Ni(II), and Cu(II) complexes with a Schiff base ligand containing thiocarbamide group

A Schiff base ligand containing thiocarbamide group of 4-phenyl-1-(4-methoxyl-1-phenylethylidene)thiosemicarbazide (HL) and its three mononuclear metal complexes of ZnL₂ (1), NiL₂ (2), and CuL₂ (3) have been synthesized. Elemental analysis, IR, and X-ray single crystal diffraction characterizations for the ligand and the three complexes have been carried out. In the three complexes, the central metallic ions of Zn²⁺, Ni²⁺, and Cu²⁺ coordinate with two deprotonated ligands of L⁻, respectively. In 1, Zn²⁺ ion adopts a distorted tetrahedral geometry, while in 2 and 3, both the Ni²⁺ and Cu²⁺ ions possess distorted square planar configurations. For the four compounds, UV–Vis spectra have been measured and DFT calculations at B3LYP/LANL2DZ level of theory prove that the electronic spectra of HL and 1 are corresponding with electronic transitions of n → π* and π → π* in the ligand itself and the electronic spectra of 2 and 3 are attributed to intraligand electronic transitions as well as d–d electronic transitions. Electrochemical investigations reveal that the different metal–ligand interactions have changed the peak shapes and peak locations, which are corresponding with the DFT-B3LYP/LANL2DZ calculational results. Fluorescence spectra measurements indicate that the ligand emits purple fluorescence and the complex 1 emits stronger blue fluorescence, while the complexes 2 and 3 quench fluorescence. The thermal analyses result show that the three complexes undergo two similar decomposition processes because of their similar geometric configurations.     

Two chiral mononuclear and one-dimensional cadmium(II) complexes constructed by (1R,2R)-N1,N2-bis(pyridinylmethyl)cyclohexane-1,2-diamine derivatives: Effect of positional isomerism

Reactions of (1R,2R)-N¹,N²-bis(pyridinylmethyl)cyclohexane-1,2-diamine derivatives, (1R,2R)-2-bpcd and (1R,2R)-3-bpcd [(1R,2R)-2-bpcd = (1R,2R)-N¹,N²-bis(pyridin-2-ylmethyl)cyclohexane-1,2-diamine, (1R,2R)-3-bpcd = (1R,2R)-N¹,N²-bis(pyridin-3-ylmethyl)cyclohexane-1,2-diamine], with CdI₂ in an analogous way led to the formation of a chiral discrete mononuclear complex and a chiral one-dimensional polymeric chain, respectively, which may be attributed to the positional isomerism of the ligands. The chiral organic ligands and complexes display luminescent properties indicating that they may have a potential application as optical materials. Powder second-harmonic generation (SHG) efficiency measurement shows that the SHG efficiency of the complexes is approximately 0.3 and 0.45 times that of KDP, respectively.