Enhanced circular dichroism at elevated temperatures through complexation-induced transformation of a three-layer cyclophane with dualistic dynamic helicity

• Katoono, Ryo

• Obara, Yudai

• Fujiwara, Kenshu

• Suzuki, Takanori

Abstract

When two planes stacked one above the other are twisted, they provide a dynamic pair of helical conformations with (M)- or (P)-helicity. We designed a three-layer cyclophane that consists of two such dynamic pairs: the top and middle planes, and the middle and bottom planes. Hence, several global conformations could be created for the overall molecule, e.g., double-helical forms with a pair with the same helicity [(M, M) or (P, P)], and a meso-like form with a pair with a different helicity (M, P). These conformations dynamically interconvert to each other in solution. Chiroptical properties were given by the helical-sense preference of the double-helical forms, which was brought about through complexation with a chiral hydrogen-bonding guest. In terms of the conformational energy in a complexed state, when a desirable relationship between double-helical and meso-like forms was attained, complexation-induced circular dichroism was enhanced at elevated temperatures and decreased at lowered temperatures.

Journal

• Chemical science

  Chemical science 9 (8), 2222-2229, 2018-02-28

  Royal Society of Chemistry

Keywords

• General Chemistry

Details

• CRID: 1050282676658448768
• NII Article ID: 120006473606
• NII Book ID: AA12555653
• DOI: 10.1039/c7sc05242a
• ISSN: 20416539
• ISSN: 20416520
• HANDLE: 2115/70694
• Web Site: http://pubs.rsc.org/en/content/articlepdf/2018/SC/C7SC05242A
• Text Lang: en
• Article Type: journal article
• Data Source:
  • IRDB
  • Crossref
  • CiNii Articles
  • KAKEN