One-step synthesis of [16]helicene

Kazuyuki Mori; Takashi Murase; Makoto Fujita

doi:10.1002/anie.201502436

One-step synthesis of [16]helicene

Angew Chem Int Ed Engl. 2015 Jun 1;54(23):6847-51. doi: 10.1002/anie.201502436. Epub 2015 Apr 23.

Authors

Kazuyuki Mori¹, Takashi Murase², Makoto Fujita³

Affiliations

¹ Department of Applied Chemistry, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan).
² Department of Material and Biological Chemistry, Faculty of Science, Yamagata University, 1-4-12 Kojirakawa-machi, Yamagata-shi, Yamagata 990-8560 (Japan). tmurase@sci.kj.yamagata-u.ac.jp.
³ Department of Applied Chemistry, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan). mfujita@appchem.t.u-tokyo.ac.jp.

PMID: 25907312
DOI: 10.1002/anie.201502436

Abstract

A single-strand arylene-vinylene precursor containing four phenylene and three naphthylene units linked together with six vinylene spacers undergoes helical folding via sextuple photocyclization to give a [16]helicene core in a single step. The phenylene and naphthylene units are arranged in the precursor such that unfavorable side reactions (anthracene or benzoperylene formation) are avoided, and this is the key to the success of the one-step synthesis of [16]helicene, which is the longest [n]helicene that has been synthesized to date.

Keywords: helical structures; photocyclization; polycyclic aromatic compounds; regioselectivity; π-π interactions.