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1.
手性配合物模板剂对磷酸锌骨架的手性传递   总被引:1,自引:0,他引:1       下载免费PDF全文
以外消旋的钴胺配合物Co(en)3Cl3为模板剂,在水热体系中合成出二种新颖的磷酸锌化合物:[Co(en)3]·[Zn8P6O24Cl]·2H2O(1)和[Co(en)3]2·[Zn6P8O32H8](2  相似文献   

2.
One kind of novel chiral porphyrin and its zinc complex were synthesized and characterized. The molecular recognition of chiral zinc porphyrin towards amino acid esters in CHCl3 was investigated by UV‐vis spectral titration method. The associative constants of the molecular recognition reactions were all KD>KL and followed the order of K(PheOMe)>K(LeuOMe)>K(ValOMe)>K(AlaOMe) in host (Zn(L‐BocTyr)TAPP). Circular dichroism spectra were used to explain chiral molecular recognition. The minimal energy conformation of host‐guest molecular system was sought by molecular dynamics method. The molecular recognition process of this host‐guest system was calculated by quantum chemistry and the results were explained by the experiments  相似文献   

3.
Abstract

In a model study, various zinc salts are shown to behave as efficient nucleophilic reagents in mild conditions for unequivocal inversion of (?) menthol to (+) neomenthyl derivatives.  相似文献   

4.
苯丙氨酸桥联手性锌双卟啉受体对胺的分子识别   总被引:3,自引:2,他引:1  
金属卟啉的分子识别研究是当今卟啉仿生化学的重要课题.手性金属卟啉作为光学活性分子的对映选择识别受体和手性核磁共振试剂[1]尤为引人注目.  相似文献   

5.
手性锌卟啉与氨基酸酯的分子识别性能   总被引:1,自引:0,他引:1  
通过紫外-可见光谱滴定法, 研究了手性锌卟啉配合物[p-(L-Leu)C2O-TPPZn]与手性氨基酸酯客体在CHCl3中的分子识别行为. 实验结果表明, D型氨基酸酯的缔合常数比L型的大, 且缔合常数按K(AlaOCH3)相似文献   

6.
氨基酸桥联新型手性锌双卟啉配合物的合成与表征   总被引:5,自引:2,他引:5  
生命系统中的金属卟啉生物大分子在卟啉的Soret带均表现出诱导圆二色性(InducedFig.1Structureofaminoacidbridgedzincpor┐phyrindimerO,O┐C2┐AA┐C2┐(TPP)2Zn2R=Bn,AA=P...  相似文献   

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以zn为催化剂,手性氮杂环丁酮和γ卤代的β-酮酯为原料,合成了两个手性二氢吡啶酮衍生物,其结构经1^H NMR和MS确证。  相似文献   

9.
在纳秒(ns)领域中,利用Z-扫描技术测定了Zn(o-BocTyr)TAPP(主体1)和Zn(p-BocTyr)TAPP(主体2)两种手性锌卟啉的三阶非线性光学性质以及对咪唑类客体的分子识别行为的构象研究. 结果表明,(1) 两种手性锌卟啉都具有反饱和吸收效应和自散焦效应;(2) 由于两种主体中侧链位置的差异,造成两种主体分子极化程度的不同,主体1具有较大的三阶非线性折射率(n2)值;(3) 主体1中侧链苯环与卟啉环之间存在一定的相互作用;(4) 分子识别出现了配位方向的选择性,客体咪唑(Im)与主体1侧链中的苯环能够形成π-π相互作用,选择从有侧链一方配位于主体1,而2-甲基咪唑(2-MeIm)选择从没有侧链一方进攻主体1,但对于主体2,则没有出现配位方向的选择性.  相似文献   

10.
Supermolecular chemistry is the chemistry involved molecular bond. A Seris of function studies on supermolecular recognition, assembly, reaction and catalysis etc.  相似文献   

11.
The most effective catalyst system for the enantioselective alkylation of an aldehyde on the basis of “asymmetric activation” can be found by super high throughput screening of chiral ligands (L*) and activators (A*) for the diethylzinc complex. The product, an optically active alcohol, could be obtained with 99% ee and in up to 100% yield (see reaction scheme). R=benzylidene.  相似文献   

12.
Static second-order nonlinear optical effects of amino acid zinc(II) porphyrins 1, 2, 3 and 4 were calculated by the TDHF/PM3 method based on the molecular structures optimized at the semiempirical PM3 quantum chemistry level, showing due to the cancellation of symmetric center, these amino acid zinc(II) porphyrins exhibit second order nonlinear optical response. The analysis of β components indicated that these amino acid zinc(II) porphyrins are of multipolarizabilities, and they may be ascribed as the "mixture" of octupolar and dipoar molecules with ||βJ=3||/||βJ=1|| ≈ 5. It is found that there are no significant differences between the static β values of non-chiral and chiral amino acid zinc(II) porphyrins. However, the βxyz component, which is quite important to quadratic macroscopic х (2) susceptibility of chiral material, is increased significantly with the increase of side chain group of amino acids.  相似文献   

13.
Catalytic asymmetric carbon-carbon bond formation is one of the most important reactions and have attracted much attention to develop more efficient enantioselective C-C formation methods in organic synthesis. In this field, asymmetric addition of diethylzinc to aldehydes[1] and conjugate addition to enones[2] have drawn special interests and have been greatly developed. Regardless of it, much spaces in these areas still exist, so it needs more extensive and intensive researches for the purpose of as follows: (1) attaching ligands to a polymer for the easy separation of the catalysts so as to be able to allow very efficient recovery and reuse of the catalysts, and the possibility of carrying out the desired transfomation in continuous mode in a flow reactor, etc., (2) searching for novel chiral catalysts with such features as more suitable for more extensive substrates varieties, and more convenient and economical as well as possessing applicable prospect, and so on. Here we report some works in these areas done in our laboratory.  相似文献   

14.
The first highly enantioselective nucleophilic addition reaction of phosphites with 2H-azirines has been developed. The reaction was applied to various 3-substituted 2H-azirines using novel chiral bis(imidazoline)/ZnII catalysts to afford products in good yield with high enantioselectivity. The transformation of the obtained optically active aziridines showed that 2H-azirines act as either α,β- or β,β-dicarbocationic amine synthons.  相似文献   

15.
This note explains the relationship (as well as the absence of a relationship) between chiral space groups and chiral molecules (which have absolute configurations).For a chiral molecule,which must crystallize in a chiral space group,the outcome of the absolute configuration determination must be linked to some other properties of the chiral crystal such as its optical activity for the observation to the relevant.  相似文献   

16.
A new chiral tetradentate ligand (S,S)-1,5-bis (4-benzyloxazolin-2-yl-methyl)-1,5-diazacyclo-octane I has been synthesized and the application of 1 as catalyst in the enantioselective addition of diethyl zinc to benzaldehyde is also described.  相似文献   

17.
采用高效液相色谱法,在自制的纤维素-三(3,5-二甲基苯基氨基甲酸酯)(ATEO-OD)、纤维素-三(4-甲基苯基氨基甲酸酯)(ATEO-OG)和纤维素-三(4-甲基苯基甲酸酯)(ATEO-OJ)3种手性柱上对16种不同结构的手性化合物进行了拆分和比较.试验结果表明:16个手性样品在这3种手性固定相上分别获得了不同程度的拆分,A TEO-OD对所分析样品具有更好的手性识别能力,ATEO-OG和ATEO-OJ的手性识别能力相当.  相似文献   

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