A new heterocyclic skeleton with highly tunable absorption/emission wavelength via H-bondingElectronic supplementary information (ESI) available: Copies of 1H and 13C NMR spectra for all new compounds, X-ray data, photophysical data and computational details. CCDC 1407107, 1407108, 1407277 and 1412486. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c5ra17755c

• Main Authors: Tomashenko, Olesya A, Khlebnikov, Alexander F, Mosiagin, Ivan P, Novikov, Mikhail S, Grachova, Elena V, Shakirova, Julia R, Tunik, Sergey P
• Format: Article
• Language: English
• ISSN: 2046-2069
• DOI: 10.1039/c5ra17755c

A new heterocyclic system, pyrido[2,1- a ]pyrrolo[3,2- c ]isoquinoline, was synthesized via Pd-catalyzed intramolecular cyclization of 1-[1-benzyl-2-(2-bromophenyl)-1 H -pyrrol-3-yl]pyridin-1-ium bromides. The heterocycles obtained display stimuli responsive fluorescence in solution depending on the nature of the solvent. The strongest blue shift of the emission maxima and growth in luminescence intensity was observed in protic solvents and upon addition of proton donors to solutions of compounds in aprotic solvents. The effect of proton donors on emission characteristics was explained by DFT calculations in terms of H-complex formation with the nucleophilic centres of the molecular skeleton. A new heterocyclic system, pyrido[2,1- a ]pyrrolo[3,2- c ]isoquinoline, showing stimuli responsive fluorescence, was synthesized via Pd-catalyzed intramolecular cyclization of 1-[1-benzyl-2-(2-bromophenyl)-1 H -pyrrol-3-yl]pyridin-1-ium bromides.