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Isolation of a chiral anthracene cation radical: X-ray crystallography and computational interrogation of its racemization.

ABSTRACT: Chiral cation-radical salts hold significant promise as charge-transfer materials, chiroptical switches, and electron-transfer catalysts for enantioselective synthesis. Herein we demonstrate that the readily-available chiral 9,10-diphenyleanthracene derivative (i.e.SANT) forms a robust cation radical, whose structure was elucidated by X-ray crystallography and DFT calculations. While SANT was observed to racemize on a timescale (t1/2) of 1.1 hours, a computational conformational search and kinetic analysis of the racemization pathway led us to identify a simple methyl substituted SANT derivative, which does not racemize (racemization t1/2 1013-1017 years).

SUBMITTER: Ivanov MV

PROVIDER: S-EPMC5465818 | biostudies-literature | 2017 Feb

REPOSITORIES: biostudies-literature

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Isolation of a chiral anthracene cation radical: X-ray crystallography and computational interrogation of its racemization.

Ivanov Maxim V MV Thakur Khushabu K Bhatnagar Anshul A Rathore Rajendra R

Chemical communications (Cambridge, England) 20170201 18

Chiral cation-radical salts hold significant promise as charge-transfer materials, chiroptical switches, and electron-transfer catalysts for enantioselective synthesis. Herein we demonstrate that the readily-available chiral 9,10-diphenyleanthracene derivative (i.e.SANT) forms a robust cation radical, whose structure was elucidated by X-ray crystallography and DFT calculations. While SANT was observed to racemize on a timescale (t1/2) of 1.1 hours, a computationa ...[more]

PMID: 28203653

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