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101.
A practical synthesis of ortho-silyl-substituted phenol from ortho-bromophenyl silyl ethers without using RLi is described. Various ortho-bromophenyl silyl ethers are treated with commercially available Mg turnings, which are easy to handle in air, and transfer of the silyl group to the ortho-position occurs in good to high yields. Selective mono-magnesiation of 2,6-dibromophenyl silyl ether is observed even in the presence of excess Mg, and ortho-bromo-6-silylphenol is obtained as the predominant product. The obtained ortho-silyl-substituted phenol is formylated with (CH2O)n/MgCl2/Et3N, and then condensation with a diamine leads to a silyl-substituted salen-type ligand in a good yield. This scheme is suitable for the large scale synthesis of silyl-substituted salen-type ligands bearing imine groups. 相似文献
102.
采用温和的化学表面改性和自组装方法成功制备了埃洛石纳米管负载salen钼(HNTs-SL-Mo)催化剂,运用透射电镜、X射线衍射、红外光谱、诱导偶合等离子体谱和X射线光电子能谱表征了催化剂的形态、大小和分散性等性质。结果证明了salen结构的存在和埃洛石配位钼催化剂的成功制备。制备的催化剂在各种烯烃的环氧化反应中均有很好的活性,且活性高于均相催化剂。对比实验表明,在固定MoO(O2)2(DMF)2时, salen结构发挥了重要作用,不能用N原子作为单一配体来代替。本文还推测了钼和salen配体可能的连接方式和该催化剂催化烯烃环氧化反应的机理。该催化剂在重复使用8次后其活性未见明显下降,表现出优异的重复使用性能。由于埃洛石是一种廉价易得的材料,因此它可为设计效果独特的催化剂提供一个选择。 相似文献
103.
Rui Jia Ting Gao Yu Yang Wenbin Sun Ruoxi Chen Pengfei Yan Guangfeng Hou 《无机化学与普通化学杂志》2015,641(11):1974
The luminescence properties of the tetranuclear bimetallic lanthanide complexes Sm2Eu2 ( 1 ) and Eu2Tb2 ( 2 ), were compared with those of the analogous homometallic complexes [Sm4(μ3‐OH)2(salen)2(acac)6(CH3OH)2] · CH3OH ( 3 ) and [Eu4(μ3‐OH)2(salen)2(acac)6(CH3OH)2] ( 4 ) [H2salen = N, N′‐ethylenebis(salicylideneimine), Hacac = acetylacetonate]. X‐ray crystallographic analysis reveals that complexes 3 and 4 have planar tetranuclear structures. For the Eu2Tb2 configurational isomer, the TbIII ion in complex 2 mainly serves as a sensitizer. The quantum yields and lifetime measurements for 2 support the premise that Ln/Ln energy transfer occurs in such lanthanide bimetallic complexes, along with the usual ligand‐to‐metal triplet energy pathways. Complexes 3 and 4 exhibit the characteristic metal‐centered emission. 相似文献
104.
Hao-Yan Yin Jiu-Jiao Gao Xuemin Chen Bin Ma Zi-Shu Yang Dr. Juan Tang Prof. Bing-Wu Wang Prof. Tianfeng Chen Prof. Chu Wang Prof. Song Gao Prof. Jun-Long Zhang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(45):20322-20328
Gallium(III)-based drugs have gained momentum in cancer therapy due to their iron-dependent anticancer activity. Judicious choice of ligands is critical for improved oral bioavailability, antitumor efficacy, and distinct mechanisms from simple GaIII salts. We describe GaIII complexes with planar tetradentate salen ligands [salen=2,3-bis[(4-dialkylamino-2-hydroxybenzylidene)amino]but-2-enedinitrile)] and labile axial solvent ligands, which display tumor growth inhibition in vitro and in vivo comparable to cisplatin. Confocal fluorescence microscopy, western blotting, mRNA profiling, chemical proteomics, and surface plasmon resonance (SPR) studies provide compelling evidence that PDIA3, a member of the protein disulfide isomerase (PDI) family involved in endoplasmic reticulum (ER) stress, is a direct target of Ga-1 . This work offers a new route to designing and synthesizing Ga-based drugs, and also reveals that PDIA3 is an important anticancer target. 相似文献
105.
The series of salen-bridged bis-pillar[1]arenes were conveniently prepared by condensation reaction of5,5'-methylenebis(2-hydroxybenzalde hyde)or 5,5'-(propane-2,2-diyl)bis(2-hydroxybenzaldehyde)with mono-amido-functionalized pillar[5]arenes containing different terminal aminoalkyl groups in refluxing ethanol.The^1H NMR and 2D-NOESY spectra indicated that the salen-bridged bis-pillar[5]arenes with longer allcylene linker(n=3,4,6)formed the fascinating bis-[1]rotaxanes,while the salenbridged bis-pillar[5]arenes with short hydrazine and ethylenediamino linker(n=0,2)predominately existed in free form.The single crystal structure of the bis-pillar[5]are ne ambiguously indicated that two propylenediamino linker inserted in to two cavities of pillar[5]arene to form a novel bis-[1]rotaxanes. 相似文献
106.
Ye Qian Wen Wei Min Ren Xiao Bing Lu State Key Laboratory of Fine Chemicals Dalian University of Technology Dalian China 《中国化学快报》2011,(11)
A novel enantiopure salen ligand bearing a diphenylphosphine oxide on the 3-position of one aromatic ring was synthesized and combined with Ti(Oi-Pr)_4 as a monometallic bifunctional catalyst for asymmetric cyanosilylation reaction of aldehydes with tnmethylsilyl cyanide(TMSCN).The catalyst system exhibited excellent activity and moderate enantioselectivity.The addition of TMSCN to 4-nitrobenzaldehyde in the presence of 1 mol%catalyst loading could complete within 10 min at ambient temperature. An intram... 相似文献
107.
108.
109.
新型双芳烃桥连的salen钛配合物是一种高活性的催化三甲基硅腈对醛不对称加成反应的催化剂,底物与催化剂用量比率可达1 000:1.由(R,R)-1,2.环已二胺和3,5-二叔丁基水杨醛合成的催化剂4在催化三甲基硅腈对醛不对称加成反应中达到87%的对映选择性. 相似文献
110.
《Journal of Coordination Chemistry》2012,65(21):3661-3669
An organic–inorganic hybrid based on Mn-salen and decavanadate, [NH4]2[Mn(salen)(H2O)2]4[V10O28]?·?6H2O (1) (salen?=?N,N′-ethylene-bis(salicylideneiminate)), has been synthesized by the strategy of secondary building units in mixed methanol–water solution and was structurally characterized by single-crystal X-ray diffraction, elemental analyses, IR, and UV-Vis. The [Mn(salen)(H2O)2]+ cations and water molecules are located in the interspaces among the polyoxoanions [V10O28]6? forming a POM-based supramolecule. Compound 1 is the first example of metal-Schiff-base polyoxovanadates. The photocatalytic analysis, cyclic voltammetry, and electrocatalytic analysis of 1 have been investigated. 相似文献