Synthesis and Evaluation of a 1,3a,6a-Triazapentalene (TAP)-Bonded System

A method of synthesizing a directly connected 1,3a,6a-triazapentalene (TAP) ring system as a linearly bonded aromatic system with a planar form was established. Various TAP-dimers and a 2-alkyl-TAP-trimer were synthesized and their fluorescence properties were evaluated. Although the direct connection of the TAP ring with other TAP rings did not affect the fluorescence properties in diluted solvent, TAP-dimers showed unique fluorescence properties derived from the aggregation state under highly concentrated conditions. In particular, TAP-dimer 5f showed aggregation-induced emission in highly concentrated solution, and 5b showed typical mechanochromic fluorescence in the solid state despite their compact molecular size.

This is the peer reviewed version of the following article: M. Ito, A. Mera, T. Mashimo, T. Seki, S. Karanjit, E. Ohashi, A. Nakayama, K. Kitamura, T. Hamura, H. Ito, K. Namba, Chem. Eur. J. 2018, 24, 17727, which has been published in final form at https://doi.org/10.1002/chem.201804733. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions.