The Study of The Second-Order Asymmetric Transformation in Metal Complexes

金属配合物二阶不对称转变的研究

• 批准号: 09640669
• 负责人: KITA Masakazu
• 金额: $ 2.18万
• 依托单位: NARUTO UNIVERSITY OF EDUCATION
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 1998
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09640669/
• 关键词: first-Ordter asymmetric transtormation; Second-Order asymmetric transformation; cobalt(III) complex; kinetics of Mutardation; activation energy; solubility; optical ailivity; N-(S-proline) dithiocarbamate; R-システイン; 反応速度; 活性化パラメーター; S-プロリルジチオカルバ

The spectrum of tris{N-(S-proline)dithiocarbamato}cobaltate(III) : [Co(S-prodtc)_3]^<3-> is similar to that of tris(dimethyldithiocarbamato)cobalt(III) so that the former complex shoud have [Co(S)_6] chromophore. The proline's carboxyl groups can not coordinate to cobalt(III) Ion. This complex shows mutarotation but the isomer ratio can be fixed by adsorption on anion exchange resin of QAE-Sephadex. Furthermore, he column chromatographic technique gave optically pure diastereomers. On the other hand, the second-order asymmetric transfomation in the barium salt produced the pure DELTA isomer. At low temperature (193K) the ^1H NMR spectrum of K_3[Co(S-prodtc)_3] in methanol solution shows that of the pure DELTA isomer. This system will be able to yield new informations on asymmetric transformation.The mutarotation of the fac-[Co(R-cysteinato-N,S)_3]^<3-> complex in 0.1 M Li_2(R-cysteinate) aqueous solution has been reported last year on the second-order asymmetric transformation and its kinetics. Now we also confirm that isomer ratio can be frozen by adsorption on anion exchange resin. The examination of the effect of free R- or S-cysteinate ion indicates that the inversion around cobalt center competes with the replacement of free R-cysteinate ion.

三{N-(S-脯氨酸)二硫代氨基甲酸}钴(III) : [Co(S-prodtc)_3]^<3-> 的光谱与三(二甲基二硫代氨基甲酸)钴(III) 相似，因此前者配合物应具有[Co(S)_6]发色团。脯氨酸的羧基不能与钴(III)离子配位。该配合物表现出变旋性，但异构体比例可以通过QAE-Sephadex阴离子交换树脂的吸附来固定。此外，柱色谱技术得到光学纯的非对映体。另一方面，钡盐中的二级不对称转化产生了纯的DELTA异构体。在低温(193K)下，K_3[Co(S-prodtc)_3]在甲醇溶液中的^1H NMR谱显示了纯DELTA异构体的谱。该系统将能够产生关于不对称转化的新信息。fac-[Co(R-cysteinato-N,S)_3]^<3->络合物在0.1 M Li_2(R-cysteinate)水溶液中的变旋具有去年报道了二阶不对称变换及其动力学。现在我们还证实可以通过阴离子交换树脂吸附来冻结异构体比例。对游离R-或S-半胱氨酸离子的影响的检查表明，钴中心周围的倒转与游离R-半胱氨酸离子的取代竞争。

项目成果

M.Kita and K.Yamanari: ""The Effect of Counter Cations on Second-Order Asymmetric Transformations in fac-DELTA-and A- Tris (R-cysteinato-N,S) cobaltate (III) Complexes and The Kinetics of Mutarotation"" J.Cham, Soc.Dalton Trans. (in press accepted at 18th

M.Kita 和 K.Yamanari：“抗衡阳离子对 fac-DELTA-和 A-Tris (R-cysteinato-N,S) 钴酸 (III) 配合物二阶不对称转变的影响和变旋动力学”

M.Kita: "The Effect of Counter Cations on Second-Ordor Asymmetric Transformations in fac-△-and A-Tris(R-cysteinato-NIS) cobaltate(III)Complexes and The Kinetics of Mutarotation" J.Chem.Soc.Dalton Trans(1992年2月18日受理).

M.Kita：“抗衡阳离子对 fac-△-和 A-Tris(R-cysteinato-NIS) 钴 (III) 配合物二级不对称转变的影响以及变旋转动力学”J.Chem.Soc.Dalton跨（1992 年 2 月 18 日收到）。

M.Kita: "The Effect of Counter Cations on Second-Order Asymmetric Transformations in fac-△-and ∧-Tris (R-cysteinato-N,S) cobaltate (III) Complexes and The Kinetics of Mutarotation" J.Chem,Soc.Datton Trans.(1999年2月18日受理).

M.Kita：“抗衡阳离子对 fac-△-和 ∧-Tris (R-cysteinato-N,S) 钴酸 (III) 配合物二阶不对称转变的影响以及变旋转动力学”J.Chem,Soc .Datton Trans（1999 年 2 月 18 日收到）。