Acta Chimica Sinica ›› 2008, Vol. 66 ›› Issue (2): 195-199. Previous Articles     Next Articles

Original Articles

钴卟啉对有机小分子的手性识别

莽朝永*,1,赵霞1,刘彩萍2,吴克琛*,2   

  1. (1大理学院生命科学与化学学院 大理 671000)
    (2中国科学院福建物质结构研究所 结构化学国家重点实验室 福州 350002)
  • 投稿日期:2007-01-22 修回日期:2007-08-03 发布日期:2008-01-28
  • 通讯作者: 吴克琛

Chiral Recognitions of Organic Small Molecules by Cobalt(III)-Porphyrin

MANG Chao-Yong*,1 ZHAO Xia1 LIU Cai-Ping2 WU Ke-Chen*,2   

  1. (1 College of Life Science and Chemistry, Dali University, Dali 671000)
    (2 State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002)
  • Received:2007-01-22 Revised:2007-08-03 Published:2008-01-28
  • Contact: WU Ke-Chen

Theoretical calculations on chiral discrimination of organic molecules by a chiral Co(III) α,α,β,β-tetramethylchiroporphyrin (TMCP) have been performed at the time-dependent density functional theory level. Upon taking the correction of the basis set superposition errors into consideration, molecular recognition leads to a large interaction energy, 310.5 kJ/mol for discrimination of S-prolinol by Co(III)-TMCP and 241.6 kJ/mol for discrimination of (S)-2-butylamine by Co(III)-TMCP. In addition to the coordinated bond between the host Co(III)-TMCP and the guest (S)-prolinol or (S)-2-butylamine, the hydrogen bond interactions are also an important factor in enhancing the molecular recognitions. Chiral discrimination induces remarkable differences in both electronic circular dichroism and optical rotatory power. The lowest-energy band of electronic absorption spectra originates from the host-guest charge-transfer transition (π→p*) between the HOMO and the LUMO, which causes a negative/positive Cotton effect. The higher-energy band is induced by the localized π→π* transition in the porphyrin ring, and is composed of a negative Cotton effect and a positive Cotton effect. The highest-energy band stems from the p→π* transition from the substituents to the porphyrin ring, which leads to two negative Cotton effects.

Key words: molecular recognition, chiral discrimination, porphyrin, electronic circular dichroism, density functional theory