摘要
合成了新型手性Salen配体(H3L)及新型手性Salen双核锌配合物(主体).通过研究主体对咪唑类客体及氨基酸酯类客体的分子识别行为,测定了这些配位反应的缔合常数.主体对咪唑类客体分子识别的缔合常数顺序为:K(Im)>K(2-MeIm)>K(2-Et-4-MeIm).主体对氨基酸酯类客体分子识别的缔合常数顺序为:K(LeuOCH3)>K(ValOCH3)>K(AlaOCH3)>K(SerOCH3),配位数均为2.主体与D、L型氨基酸酯分子识别反应在不同温度下的缔合常数结果表明,随着温度的升高,对映选择性下降.实验发现反应体系中存在焓熵补偿关系.CD光谱的研究结果也反映了主体对不同客体识别能力的差异.
Chiral Salen ligand(H3L) and zinc(II) dinuclear complex(host) were synthesized,which were characterized by elemental analysis, 1H NMR, UV Vis, FT IR and CD spectra.Molecular recognition behavior of the host for imidazoles and amino acid esters was studied. The binding constants between host and guest were measured, and it shows that the binding constants decrease in the orders of K(Im) >K(2 MeIm) >K(2 Et 4 MeIm) (imidazoles) and K(LeuOCH3) >K(ValOCH3) >K(AlaOCH3) >K(SerOCH3) (amino acid esters), and the coordination number is 2. The enthalpy entropy compensation existed in host guest system. By studying the binding constants between the host and amino acid esters, we find that the enantiosel ectivity decreases as the temperature increases. The studies of circular dichroism spectra of host guest system show that the recognition behavior is different for various guests.
出处
《物理化学学报》
SCIE
CAS
CSCD
北大核心
2004年第5期529-534,共6页
Acta Physico-Chimica Sinica
基金
国家自然科学基金(20171024
20271030)
天津市自然科学基金(023604011)
教育部留学回国人员科研基金资助项目~~
关键词
手性Salen双核锌配合物
分子识别技术
缔合常数
温度
圆二色光谱
催化反应
Chiral Salen (N,N′ bis (salicylaldehyde ethylenediimine)) zinc(II)dinuclear complex, Molecular recognition, Circular dichroism spectra
