Control of Guest Inclusion and Chiral Recognition Ability of 6‐ O ‐Modified β‐Cyclodextrins in Organic Solvents by Aromatic Substituents at the 2‐ O Position
Control of Guest Inclusion and Chiral Recognition Ability of 6‐ O ‐Modified β‐Cyclodextrins in Organic Solvents by Aromatic Substituents at the 2‐ O Position
复制标题
2-O 位芳香族取代基对有机溶剂中 6-O-改性 β-环糊精的客体包合和手性识别能力的控制
DOI：
10.1002/cplu.202000522
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发表时间：
2020
期刊：
影响因子：
3.4
通讯作者：
Kida Toshiyuki
中科院分区：
文献类型：
--
作者：
Kalaw Justine M.;Yamamoto Ryusuke;Kogame‐Asahara Chizuru;Shigemitsu Hajime;Kida Toshiyuki
环糊精在水介质中的主客体化学和应用已经很成熟。然而，缺乏对有机溶剂的全面研究。在这里，我们报告了在2-位带有各种芳香族取代基的6-O-叔丁基二甲基甲硅烷基化β-环糊精（TBDMS-β-CD）的设计和合成，以及它们在非极性有机溶剂中与芳香族客体形成的包合物。与母体 TBDMS-β-CD 相比，这些衍生物通过与 CD 空腔和 2-位芳香族取代基的协同客体结合，对芘的包合能力至少提高了 10 倍。芳香族取代基的类型很大程度上影响TBDMS-β-CD对环己烷中1-(1-萘基)乙胺的手性识别能力。具有对甲苯基取代基的 TBDMS-β-CD 衍生物相对于相应的 (R)-异构体对 (S)-1-(1-萘基)乙胺具有显着的手性选择性 (KS/KR=4.1±0.5)，而具有 2-吡啶甲基取代基的 TBDMS-β-CD 衍生物则表现出反手性选择性 (KR/KS=8.7±0.6)。
The host‐guest chemistry and applications of cyclodextrins in aqueous media is well established. However, a comprehensive study in organic solvents is lacking. Here, we report the design and synthesis of 6‐O‐tert‐butyldimethylsilylated β‐cyclodextrin (TBDMS‐β‐CD) bearing various aromatic substitutions at the 2‐Oposition and their inclusion complex formation with aromatic guests in nonpolar organic solvents. Compared to the parent TBDMS‐β‐CD, these derivatives exhibit at least a 10‐fold increase in inclusion ability toward pyrene through cooperative guest binding with the CD cavity and the aromatic substituents at the 2‐Oposition. The type of the aromatic substituent largely affects the chiral recognition ability of TBDMS‐β‐CD toward 1‐(1‐naphthyl)ethylamine in cyclohexane. A TBDMS‐β‐CD derivative with ap‐tolyl substituent has a remarkable chiral selectivity for the (S)‐1‐(1‐naphthyl)ethylamine over the corresponding (R)‐isomer (KS/KR=4.1±0.5), whereas a TBDMS‐β‐CD derivative with a 2‐picolyl substituent shows the inverse chiral selectivity (KR/KS=8.7±0.6).