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A novel chiral Salen ligand with a glucose moiety was synthesized from the condensation of 1,2:5,6-di-O-isopropylidene-3-O-methylene-[5-(3-tert-butyl-2-hydroxy benzaldehyde)]-α-D-glucofuranose with (1R,2R)-1,2-diaminocyclohexane. Several chiral complexes of Mn3+, Fe3+, Co2+ and Cu2+ were prepared from this ligand. Both the ligand and the complexes were characterized by elemental analysis, NMR, IR, MS, and UV-Vis.  相似文献   
2.
环己二胺类手性席夫碱配体的合成与表征   总被引:1,自引:1,他引:0  
以(R,R)-1,2-环己二胺为手性源,同水杨醛及带有叔丁基,溴或硝基的取代水杨醛反应合成了5个手性席夫碱配体。其结构经^1H NMR,^13C NMR,IR和MS表征,并测定了其熔点和比旋光度。  相似文献   
3.
New hybrid silica-based materials containing a chiral diamine ligand have been prepared by using primary amines as templates. Amorphous materials with high porosities and high surface areas have been characterized. They have been used to immobilize chiral rhodium complexes which catalyse the enantioselective reduction of acetophenone by hydride transfer, with low enantiomeric excess.  相似文献   
4.
Seven dinuclear platinum(II) complexes with a novel chiral tetradentate ligand, (1R,1′R,2R,2′R)‐N1,N1′‐(1,4‐phenylenebis(methylene))dicyclohexane‐1,2‐diamine, were designed, synthesized and spectrally characterized. All the complexes were evaluated for their in vitro cytotoxicity against human HepG‐2, A549, HCT‐116 and MCF‐7 cancer cell lines. The results indicated that all compounds showed positive biological activity against HepG‐2, A549 and HCT‐116 cancer cell lines. In particular, compounds D7 and D2 showed better activity than carboplatin against HepG‐2 and A549 and compound D7 also showed an activity close to that of oxaliplatin. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
5.
A number of novel chiral diamines 3 , (1R,2R)‐N‐monoalkylcyclohexane‐1,2‐diamines, were designed and synthesized from trans‐cyclohexane‐1,2‐diamine and applied to the catalytic asymmetric Henry reaction of benzaldehyde and nitromethane to provide β‐nitroalcohol in high yield (up to 99%) and good enantiomeric excess (up to 89%). By using ligand (1R,2R)‐N1‐(4‐methylpentan‐2‐yl)cyclohexane‐1,2‐diamine ( 3g ), the reaction was optimized in terms of the metal ion, temperature, solvent and base. Further experiments indicated that the complex, 3g –Cu(OAc)2, was an efficient catalyst in the asymmetric Henry reaction between different aldehydes and nitromethane, and the desired products have been obtained with high chemical yields (up to 99%) and high enantiomeric excess (up to 93%). The optimized catalyst promoted the diastereoselective Henry reaction of various aldehyde substrates and nitroalkane, which gave the corresponding anti‐selective adduct with up to 99% yield and 83:17 anti/syn selectivity. Upon scaling up to gram quantities, the β‐nitroalcohol was obtained in good yield (96%) with excellent selectivities (93% ee). The chiral induction mechanism was tentatively explained on the basis of a previously proposed transition‐state model. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
6.
A chiral polymer incorporating an (R,R)-salen moiety was synthesized by the polymerization of (R,R)-1,2-diaminocyclohexane with 2,5-dibutoxy-1,4-di(salicyclaldehyde)-1,4-diethynyl-benzene by a nucleophilic addition-elimination reaction. The fluorescence responses of the (R,R)-salen-based polymer toward various metal ions were investigated by fluorescence spectra. Compared with other cations, such as Na(+), K(+), Mg(2+), Ca(2+), Mn(2+), Fe(2+), Fe(3+), Co(2+), Ni(2+), Cu(2+), Ag(+), Cd(2+), Hg(2+), and Pb(2+), Zn(2+) can lead to a pronounced fluorescence enhancement as high as 7.8-fold together with an obvious blue-shift change of the chiral polymer. More importantly, the fluorescent color of the polymer changed to bright blue instead of weak yellow after addition of Zn(2+), which can be easily detected by the naked eye. The results indicate that this kind of chiral polymer, incorporating an (R,R)-salen moiety as a receptor in the main chain backbone, can exhibit high sensitivity and selectivity for Zn(2+) recognition.  相似文献   
7.
The effects of the partial substitution of 1,4‐disubstituted cyclohexane monomers for linear aliphatic monomers in polyamides are discussed. More specifically, the relation between the stereochemistry of the cycloaliphatic residues and the thermal properties [melting temperature (Tm) and crystallization temperature (Tcr)] was investigated. For this purpose, two different types of copolyamides were synthesized: in polyamides 12.6, the adipic acid residues were partially replaced by cis/trans‐1,4‐cyclohexanedicarboxylic acid (1,4‐CHDA), whereas in polyamides 4.14, the 1,4‐diaminobutane residues were partially substituted with cis/trans‐1,4‐diaminocyclohexane (1,4‐DACH). For both systems, increasing the degree of substitution of cycloaliphatic residues for linear aliphatic residues resulted in a rise of both Tm and Tcr. This points to the isomorphous crystallization of the linear and cycloaliphatic residues. In contrast to the use of 1,4‐DACH as a comonomer, 1,4‐CHDA residues showed isomerization upon thermal treatment of the polyamides. This isomerization of the cyclohexane residues influenced the thermal properties of the copolyamides. The use of a nonisomerizing cis–trans mixture of 1,4‐DACH exhibited the large influence of the stereochemistry of the cycloaliphatic residues on the Tm of the copolyamides. For both the 1,4‐CHDA‐ and 1,4‐DACH‐based copolyamides, differential scanning calorimetry analysis revealed that recrystallization occurs during melting. This exothermal effect becomes less pronounced with an increasing content of rigid cycloaliphatic residues. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 1962–1971, 2002  相似文献   
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