Publications and Research
Document Type
Article
Publication Date
10-26-2017
Abstract
Photoluminescent divinylbipyrroles were synthesized from 3,3′,4,4′-tetraetyl-2,2′-bipyrrole-5,5′-dicarboxaldehyde and activated methylene compounds via aldol condensation.For mechanistic clarity, molecular structures of Meldrum’s acid- and 1,3-dimethylbarbituricacid-derived divinylbipyrroles were determined by single-crystal X-ray diffraction. Photoluminescentproperties of the synthesized divinylbipyrroles in dichloromethane were found to be dependent onthe presence of electron withdrawing groups at the vinylic terminal. The divinylbipyrroles derivedfrom malononitrile, Meldrum’s acid, and 1,3-dimethylbarbituric acid showed fluorescent peaks at553, 576, and 602 nm respectively. Computational studies indicated that the alkyl substituents on thebipyrrole 3 and 3′positions increased energy level of the highest occupied molecular orbital (HOMO)compared to the unsubstituted derivatives and provided rationale for the bathochromic shift of theultraviolet-visible (UV-Vis) spectra compared to the previously reported analogs.
Comments
This article was originally published in Molecules, available at DOI:10.3390/molecules22111816.
This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY 4.0) license (http://creativecommons.org/licenses/by/4.0/).