Events

Date: 20 November 2024   Time: 14:00 - 15:00

Location: Bancroft David Sizer LT

1,4-Dihydropyrrolo[3,2-b]pyrrole and Dipyrrolonaphthyridinedione – Novel Building Blocks for Optoelectronics
Daniel T. Gryko
Institute of Organic Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland.
E-mail: dtgryko@icho.edu.pl
Recently we have discovered and optimized the first practical synthesis of non-fused pyrrole[3,2-b]pyrroles via domino reaction of aldehydes, primary amines, and butane-2,3-dione.1 Six bonds are formed in heretofore unknown tandem process, which gives rise to substituted pyrrole[3,2-b]pyrroles – the 'missing link' on the map of aromatic heterocycles. Unparalleled simplicity and versatility of this one-pot reaction, non-chromatographic purification and superb optical properties (including strong violet, blue or green fluorescence both in solution as well as in the solid state), brought these molecules from virtual non-existence to the intensively investigated area functional π-systems. The parent 1,4-dihydro-pyrrolo[3,2-b]pyrroles served as building block to construct various π-expanded analogs including nitrogen-embedded buckybowl with inverse Stone–Thrower–Wales topology2,3 and diindolo[2,3-b:2',3'-f]pyrrolo[3,2-b]pyrroles. These compounds constitute the most electron-rich ladder-type heteroacenes known to date - EHOMO was located at ca. −4.6 eV. Recently, we have proved that the dipyrrolonaphthyridinedione (DPND) core constitutes an excellent scaffold for the design of strongly fluorescent dyes or quadrupolar-type materials with large two-photon absorption (TPA) cross-sections (up to 5,180 GM).37 These properties result from an unusual arrangement of donor (pyrrole ring) and acceptor (carbonyl group) moieties within the DPND core.

References
1 M. Krzeszewski, D. Gryko and D. T. Gryko, Acc. Chem. Res., 2017, 50, 2334-2345.
2 S. Mishra, M. Krzeszewski, C. A. Pignedoli, P. Ruffieux, R. Fasel and D. T. Gryko, Nat. Commun., 2018, 1714.
3 M. Krzeszewski, Ł. Dobrzycki, A. L. Sobolewski, M. K. Cyrański, D. T. Gryko, Angew. Chem. Int. Ed., 2021, 60, 14998-15005.