Novel Alkoxy-Substituted Dipyrrins and Near-IR BODIPY Dyes—Preparation and Photophysical Properties

5 years ago

Novel Alkoxy-Substituted Dipyrrins and Near-IR BODIPY Dyes—Preparation and Photophysical Properties

Hans-Ulrich Reissig, Scheghajeh Kord Daoroun Kalai, Stefan Schoder

Starting from 3-alkoxy-2-aryl-substituted pyrroles and aromatic aldehydes, a collection of new dipyrrins was prepared. Under the standard conditions of Treibs, these were converted into the corresponding boron dipyrrins (BODIPYs). Compounds of this type with alkoxy groups at C-3 position of both pyrrole subunits are new and hence the photophysical properties of this collection of novel dipyrrins and BODIPY dyes were investigated. The dipyrrins show absorption maxima up to 596 nm and emissions of up to 677 nm. For the BODIPY series a remarkable effect of the alkoxy groups was identified, resulting in red shifts for absorptions and emissions. The compound substituted with two 2-thien-2-yl groups and a meso-C6F5 substituent shows an absorption maximum at 725 nm and emits at 754 nm and thus is a new representative of a near-IR BODIPY dye related to certain aza-BODIPYs. Our results demonstrate the influence of the alkoxy groups on the spectroscopic data and reveal the potential of 3-alkoxy-2-aryl-substituted pyrroles for the design of new fluorophores. Colorful chemistry: Starting from 3-alkoxy-substituted pyrrole derivatives and aromatic aldehydes, new dipyrrins and subsequently the corresponding BODIPY dyes were prepared. Several of the BODIPYs absorb and emit in the far-red and near-IR region.

Publisher URL: http://onlinelibrary.wiley.com/resolve/doi

DOI: 10.1002/chem.201701108