Guest Inclusion by Cyclodextrins in Nonpolar Solvents

  • Author: ChemPlusChem
  • Published Date: 20 September 2020
  • Source / Publisher: ChemPlusChem/Wiley-VCH
  • Copyright: Wiley-VCH GmbH
thumbnail image: Guest Inclusion by Cyclodextrins in Nonpolar Solvents

Related Societies

Cyclodextrins (CDs) are cyclic oligosaccharides commonly used hosts in host-guest chemistry. They have high chemical stability and can bind a wide variety of guest molecules in their cavities. The chemical modification of CDs can allow researchers to improve their inclusion ability toward guest molecules. However, their applications as hosts are usually limited to aqueous solutions and certain polar organic solvents, because the driving forces of the guest inclusion are mainly hydrophobic and van der Waals interactions.

Toshiyuki Kida and colleagues, Osaka University, Japan, have designed and synthesized 6-O-tert-butyldimethylsilylated β-cyclodextrin (TBDMS-β-CD) derivatives with various aromatic substituents at the 2-O position. This functionalization enhances the guest inclusion in organic solvents through cooperative guest binding between the CD cavity and the aromatic substituent. The team modified the 2‐OH group of TBDMS‐β‐CD via reactions with benzyl bromide, 1‐(bromomethyl)‐3‐methylbenzene, 1‐(bromomethyl)‐4‐methylbenzene, 2‐(chloromethyl)pyridine hydrochloride, or 3‐(chloromethyl)pyridine hydrochloride in the presence of sodium hydride in tetrahydrofuran (THF).

Compared to the nonmodified TBDMS-β-CD, functionalized TBDMS-β-CDs with m- and p-tolyl substituents at the 2-O position exhibit a 100-fold increase in inclusion ability toward pyrene in nonpolar solvents. Certain aromatic substituents, i.e., p‐tolyl and 2‐picolyl, can also enhance the chiral recognition ability of TBDMS-β-CD toward chiral naphthalene derivatives. The modified CDs have potential uses as catalysts for enantioselective reactions in organic solvents and as effective adsorbents for chiral chromatography.



Article Views: 915

Sign in Area

Please sign in below

Additional Sign In options

Please note that to comment on an article you must be registered and logged in.
Registration is for free, you may already be registered to receive, e.g., the newsletter. When you register on this website, please ensure you view our terms and conditions. All comments are subject to moderation.

Article Comments - To add a comment please sign in

If you would like to reuse any content, in print or online, from, please contact us first for permission. more

Follow on Facebook Follow on Twitter Follow on YouTube Follow on LinkedIn Follow on Instagram RSS Sign up for newsletters

Magazine of Chemistry Europe (16 European Chemical Societies) published by Wiley-VCH