3-Ethynyltriimidazo[1,2-<i>a</i>:1′,2′-<i>c</i>:1″,2″-<i>e</i>][1,3,5]triazine Dual Short- and Long-Lived Emissions with Crystallization-Enhanced Feature: Role of Hydrogen Bonds and π-π Interactions
Daniele Malpicci,
Daniele Maver,
Elisabetta Rosadoni,
Alessia Colombo,
Elena Lucenti,
Daniele Marinotto,
Chiara Botta,
Fabio Bellina,
Elena Cariati,
Alessandra Forni
Affiliations
Daniele Malpicci
Department of Chemistry, Università degli Studi di Milano, Via Golgi 19, 20133 Milano, Italy
Daniele Maver
Department of Chemistry, Università degli Studi di Milano, Via Golgi 19, 20133 Milano, Italy
Elisabetta Rosadoni
Department of Chemistry and Industrial Chemistry, University of Pisa, Via Moruzzi 13, 56124 Pisa, Italy
Alessia Colombo
Department of Chemistry, Università degli Studi di Milano, Via Golgi 19, 20133 Milano, Italy
Elena Lucenti
Institute of Chemical Sciences and Technologies “Giulio Natta” (SCITEC) of CNR, Via Golgi 19, 20133 Milano, Italy
Daniele Marinotto
Institute of Chemical Sciences and Technologies “Giulio Natta” (SCITEC) of CNR, Via Golgi 19, 20133 Milano, Italy
Chiara Botta
Institute of Chemical Sciences and Technologies “Giulio Natta” (SCITEC) of CNR, Via Corti 12, 20133 Milano, Italy
Fabio Bellina
Department of Chemistry and Industrial Chemistry, University of Pisa, Via Moruzzi 13, 56124 Pisa, Italy
Elena Cariati
Department of Chemistry, Università degli Studi di Milano, Via Golgi 19, 20133 Milano, Italy
Alessandra Forni
Institute of Chemical Sciences and Technologies “Giulio Natta” (SCITEC) of CNR, Via Golgi 19, 20133 Milano, Italy
Organic room temperature phosphorescent (ORTP) materials with stimuli-responsive, multicomponent emissive behaviour are extremely desirable for various applications. The derivative of cyclic triimidazole (TT) functionalized with an ethynyl group, TT-CCH, is isolated and investigated. The compound possesses crystallization-enhanced emission (CEE) comprising dual fluorescence and dual phosphorescence of both molecular and supramolecular origin with aggregation-induced components highly sensitive to grinding. The mechanisms involved in the emissions have been disclosed thanks to combined structural, spectroscopic and computational investigations. In particular, strong CH⋯N hydrogen bonds are deemed responsible, for the first time in the TT family, together with frequently observed π⋯π stacking interactions, for the aggregated fluorescence and phosphorescence.
