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Efficient synthesis of 3,6,13,16-tetrasubstituted-tetrabenzo[,,,]coronenes by selective C-H/C-O arylations of anthraquinone derivatives. | LitMetric

Efficient synthesis of 3,6,13,16-tetrasubstituted-tetrabenzo[,,,]coronenes by selective C-H/C-O arylations of anthraquinone derivatives.

Beilstein J Org Chem

Department of Chemistry, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama, Kanagawa 223-8522, Japan.

Published: March 2020

An efficient synthesis of tetrabenzo[,,,]coronene derivatives having alkyl and alkoxy substituents at the 3, 6, 13, and 16-positions was achieved based on the ruthenium-catalyzed coupling reactions of anthraquinone derivatives with arylboronates via C-H and C-O bond cleavage. The reaction sequence involving the arylation, carbonyl methylenation, and oxidative cyclization effectively provided various tetrabenzo[,,,]coronenes in short steps from readily available starting materials. Tetrabenzo[,,,]coronenes possessing two different types of substituents were obtained selectively by sequential chemoselective C-O arylation and C-H arylation. The H NMR spectra of the tetrabenzo[,,,]coronene product indicated its self-assembling behavior in CDCl.

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Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7136549PMC
http://dx.doi.org/10.3762/bjoc.16.51DOI Listing

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