Accession Number:

AD1104544

Title:

Defying strain in the synthesis of an electroactive bilayer helicene

Descriptive Note:

Journal Article - Open Access

Corporate Author:

Columbia University New York United States

Report Date:

2018-11-20

Pagination or Media Count:

6.0

Abstract:

We report the synthesis of a bilayer chiral nanographene incorporating a 7helicene scaffold and two perylene-diimide PDI subunits. Twofold visible-light-induced oxidative cyclization of a phenanthrene framework selects for the desired PDI-helicene, despite the immense strain that distinguishes this helicene from two other accessible isomers. This strain arises from the extensive intramolecular overlap of the PDI subunits, which precludes racemization, even at elevated temperatures. Relative to a smaller homologue, this PDI-helicene exhibits amplified electronic circular dichroism. It also readily and reversibly accepts four electrons electrochemically. Modifications to the core phenanthrene subunit change the fluorescence and electrochemistry of the PDI-helicene without significantly impacting its electronic circular dichroism or UV-visible absorbance.

Subject Categories:

  • Physical Chemistry

Distribution Statement:

APPROVED FOR PUBLIC RELEASE