Synthesis, Characterization, and Cation-Induced Supramolecular Structures of Photochromic Bisthienylethene-Tetraazaporphyrin Hybrids (BTE-TAPs) Bearing Crown Ether Moieties.

A series of novel tetraazaporphyrinato (TAP) copper compounds 1–5 substituted with different numbers of 15-crown-5 voids and photochromic 1,2-bisthienylethenes (BTEs) were synthesized by ‘one-pot' reaction and characterized by spectroscopic methods as well as elemental analysis. The effects of BTE and 15-crown-5 substituent number and molecular symmetry on the electronic absorption spectra, infrared spectra, photochromic performance and supramolecular structure formation induced by K+ ions have been systematically investigated. All the BTE-TAP hybrids presented photocyclization and cycloreversion with different quantum yields by irradiation with 365 and 700 nm light in CHCl3 solution, respectively. The steric hindrance derived from the BTE substituents prevents the cofacial dimerization of the compounds, and only linear dimers formed as a result. [ABSTRACT FROM AUTHOR]