Two cyclometalated Pt(ii) complexes showing reversible phosphorescence switching due to grinding-induced destruction and crystallization-induced formation of supramolecular dimer structure

Qin-Zhen Yuan; Fu-Shun Wan; Ting-Ting Shen; Deng-Ke Cao

doi:10.1039/d1ra07142d

Two cyclometalated Pt(ii) complexes showing reversible phosphorescence switching due to grinding-induced destruction and crystallization-induced formation of supramolecular dimer structure

RSC Adv. 2021 Dec 21;12(1):148-153. doi: 10.1039/d1ra07142d. eCollection 2021 Dec 20.

Authors

Qin-Zhen Yuan¹, Fu-Shun Wan¹, Ting-Ting Shen¹, Deng-Ke Cao¹

Affiliation

¹ State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing University Nanjing 210093 P. R. China dkcao@nju.edu.cn.

Abstract

Complexes [Pt(dfppy)(pbdtmi)]PF₆ (1) and [Pt(ppy)(pbdtmi)]PF₆ (2) have been constructed based on dithienylethene-based N^N ligand pbdtmi, showing supramolecular dimer structure in which two coordination cations connect each other through π⋯π stacking interaction. The crystalline state samples of both 1 and 2 reveal strong phosphorescence (emission peak: around 579 nm for 1, and 551 nm for 2). Interestingly, a grinding treatment for either 1 or 2 leads to phosphorescence switching from on-state to off-state. The subsequent crystallization with toluene recovers the initial on-state. This work discusses the relationship between the supramolecular dimer structures and the related phosphorescence switching behaviors in 1 and 2, and also explores the photochromism of pbdtmi, 1 and 2.