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

Abstract

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-C F 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.

A Time-Resolved Spectroscopic Investigation of a Novel BODIPY Copolymer and Its Potential Use as a Photosensitiser for Hydrogen Evolution

“…Immediately following excitation, a depletion is evident at ∼1547 cm −1 together with new bands at 1267, 1362, and 1452 (broad) cm −1 which are assigned to a singlet excited state of the BODIPY. Previously electron transfer dynamics for BODIPY chromophores in CH 2 Cl 2 have been reported, with a GSB at 1543 cm −1 , and ESA features at 1339, 1297, and 1507 cm −1 , respectively (Schoder et al, 2017). These spectroscopic features produced within the instrument response time in our studies, have identical lifetimes [τ = 25 (±5) ps] and are assigned to a singlet excited state (Black et al, 2017).…”

Novel Lactobacillus reuteri HI120 Affects Lipid Metabolism in C57BL/6 Obese Mice

“…However, whether cholesterol levels are affected via corresponding metabolic pathway remains unclear. We used BODIPY fluorescence (49) to label cholesterol to assess the molecular mechanism of absorption. The results revealed that CLA regulates NPC1L1 and cholesterol absorption through SREBP-2.…”

EU‐40 Materials Prize: B V. Lotsch / Ehrenmitgliedschaft in der polnischen chemischen Gesellschaft: H.‐U. Reißig / Welch Award: J. B. Goodenough

“…Mithilfe Samariumdiiodid‐unterstützter Cyclisierungen gelang ihm eine der effizientesten je beschriebenen Strychninsynthesen . Kürzlich erschien in Chemistry—A European Journal eine Arbeit von ihm über die Synthese und die Eigenschaften alkoxysubstituierter Dipyrrine . Reißig gehörte zu den Herausgebern von Liebigs Annalen und war 1995–2008 Mitglied im International Advisory Board der Nachfolgezeitschrift European Journal of Organic Chemistry .…”