Photoracemization and Deracemization of Biaryl Compounds

联芳基化合物的光外消旋化和去消旋化

基本信息

批准号：
15550083
负责人：
HATTORI Tetsutaro
金额：
$ 2.5万
依托单位：
Tohoku University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2003
资助国家：
日本
起止时间：
2003 至 2004
项目状态：
已结题

项目摘要

In this study, we have synthesized blestriarene C (2,2',7,7'-tetrahydroxy-4,4'-dimethoxy-1,1'-biphenanthrene) and its analogs by using an ester-mediated nucleophilic aromatic substitution as a key step and investigated their photoracemization under fluorescent light exposure. Racemization of 1,1'-binaphthalenes and deracemization of blestriarene C were also examined.Blestriarene C was found to racemize by exposing its solution to the light near the ^1L_b absorption band. Removal of oxygen from the solution significantly retarded the reaction, suggesting intermediary of oxygen in the racemization. Blestriarene C analogs lacking 4,4'-dimethoxy and/or 7,7'-dihydroxy groups did not racemize under the conditions, while the 7,7'-diisopropoxy derivative, as well as the unsymmetrical biphenanthrene lacking 4'-methoxy and 7'-hydroxy groups, easily racemized. The tendency toward the racemization was found to strongly correlate with the redox potential of the compounds by cyclic voltammetry (CV) experiments. Thus, the lower redox potential the compound has, the higher racemization activity it shows. Based on these observations, we proposed a feasible reaction mechanism, which involves one-electron oxidation of blestriarene C by oxygen with the aid of the fluorescent light to form a radical cation intermediate. 1,1'-Binaphthalenes having two or three hydroxy and/or methoxy groups in total on each naphthalene half did not racemize under the same conditions. These compounds did not show reversible redox behavior on the CV spectra, which should be crucial in the photoracemization.

在这项研究中，我们通过使用酯介导的核友善的芳香族芳族替代品作为关键步骤，并研究了它们的光感曝光率。还检查了1,1'-二甲乙烯的种族化和Blestriarene c的降解性。发现卵裂性C通过将其溶液暴露于 ^1L_B吸收带附近的光线通过将其溶液暴露在 ^1L_B吸收带中。从溶液中除去氧气显着阻碍了反应，这表明氧气中的氧气中的中间体。在条件下缺乏4,4'-二甲氧基和/或7,7'-二羟基群的Blestriarene c类似物并未在这种条件下进行比赛，而7,7'-二异息衍生物以及不对称的Biphenanananthrene，缺乏4'-Methoxy和7'-甲基氧基和7'-Hydroxy组，易于种族。通过环状伏安法（CV）实验，发现种族化的趋势与化合物的氧化还原电位密切相关。因此，该化合物具有较低的氧化还原电位，即它显示的较高的种族化活性。基于这些观察结果，我们提出了一种可行的反应机制，该机制涉及通过氧气借助荧光来形成自由基阳离子中间体的氧气单电子氧化。在每个萘一半的总共有两个或三个羟基和/或甲氧基的1,1'-二甲乙烯甲基苯乙烯在相同的条件下没有种族化。这些化合物在CV光谱上没有显示可逆的氧化还原行为，这对于光学化至关重要。

项目成果

期刊论文数量（39）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

T.Hattori: "Synthesis, Resolution, and Absolute Stereochemistry of (-)-Blestriarence C"J.Org.Chem.. 68・6. 2099-2108 (2003)

T. Hattori：“(-)-Blestriarence C 的合成、解析和绝对立体化学”J.Org.Chem.. 68・6 (2003)。

DOI：
发表时间：
期刊：
影响因子：
0
作者：
通讯作者：

Interconversion between syn and anti Conformations of 1,3-Bis(O-cyanomethyl)-p-tert-butylthiacalix[4]arene

DOI：
10.1246/cl.2004.184
发表时间：
2004-01
期刊：
Chemistry Letters
影响因子：
1.6
作者：
V. Bhalla;Manoj Kumar;C. Kabuto;T. Hattori;S. Miyano
通讯作者：
V. Bhalla;Manoj Kumar;C. Kabuto;T. Hattori;S. Miyano

Stereoselective dialkylation of the proximal hydroxy groups of calix-and thiacalix[4]arenes.

杯-和硫代杯[4]芳烃的近端羟基的立体选择性二烷基化。

DOI：
发表时间：
2004
期刊：
Org.Biomol.Chem. 2(6)
影响因子：
0
作者：
T.Ohmura;W Mori;H.Hiraga;M.Ono;Yuko NISHIMOTO;Hiroyuki Suga et al.;Masami Sakamoto;F.Narumi
通讯作者：
F.Narumi

Stereoselective dialkylation of the proximal hydroxy groups of calix- and thicalix[4]arenes

杯-和thicalix[4]芳烃近端羟基的立体选择性二烷基化