Rhodium-Catalyzed Intermolecular Cycloaromatization Route to Cycloparaphenylenes that Exhibit Aggregation-Induced Emission

Li-Hsiang Wang; Yuki Nagashima; Masato Abekura; Hidehiro Uekusa; Gen-Ichi Konishi; Ken Tanaka

doi:10.1002/chem.202200064

Rhodium-Catalyzed Intermolecular Cycloaromatization Route to Cycloparaphenylenes that Exhibit Aggregation-Induced Emission

Chemistry. 2022 Apr 12;28(21):e202200064. doi: 10.1002/chem.202200064. Epub 2022 Mar 15.

Authors

Li-Hsiang Wang¹, Yuki Nagashima¹, Masato Abekura², Hidehiro Uekusa², Gen-Ichi Konishi¹, Ken Tanaka¹

Affiliations

¹ Department of Chemical Science and Engineering, Tokyo Institute of Technology Ookayama, Meguro-ku, Tokyo, 152-8550, Japan.
² Department of Chemistry, Tokyo Institute of Technology Ookayama, Meguro-ku, Tokyo, 152-8550, Japan.

PMID: 35194855
DOI: 10.1002/chem.202200064

Abstract

A high-yielding new route to substituted cycloparaphenylenes has been developed via reductive aromatization of a diyne bearing two cyclohexadiene units giving a cyclophenylene-ethynylene (CPE) followed by the cationic rhodium(I)/dppe complex-catalyzed intermolecular [2+2+2] cycloaddition (cycloaromatization) of the CPE with monoynes. The thus-obtained products, substituted [8]cycloparaphenylene-triphenylenes ([8]CPPTs), exhibited definite aggregation-induced emission (AIE). This molecule is noteworthy as a novel AIE-active cycloarylene that does not have well-known AIE luminogens, such as tetraphenylethene and 1,2,4,5-tetraphenylbenzene skeletons. The single-crystal X-ray diffraction analyses of the AIE-active [8]CPPTs revealed their highly ordered packing structures in which the rotation of the triphenylene moieties is restricted.

Keywords: [2+2+2] cycloaddition; aggregation-induced emission; cycloparaphenylene-triphenylenes; cyclophenylene-ethynylenes; rhodium.

Abstract

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