title: Tandem Regioselective Substitution and Palladium-Catalyzed Ring Fusion Reaction for Core-Expanded Boron Dipyrromethenes with Red-Shifted Absorption and Intense Fluorescence.
abstract: A selective method for the core-extension of boron dipyrromethene (BODIPY) with two annulated indole rings with exclusive syn-connectivity is reported. The method is based on a regioselective nucleophilic substitution reaction of 2,3,5,6-tetrabromoBODIPY with aryl amines, followed by palladium-catalyzed intramolecular C-C coupling ring fusion. The unsymmetrical core-expanded BODIPY with annulated indole and benzofuran rings was also synthesized by stepwise and regioselective nucleophilic substitution and palladium-catalyzed intramolecular C-C coupling reaction. The diindole-annulated BODIPY was unambiguously characterized by single-crystal X-ray analysis. The optical properties of the present core-expanded BODIPYs were studied, revealing clearly red-shifted absorption and emission bands and enhanced absorption coefficients upon annulation.
authors.affiliation: The Key Laboratory of Functional Molecular Solids, Ministry of Education, Anhui Key Laboratory of Molecule-Based Materials, School of Chemistry and Materials Science, Anhui Normal University, Wuhu, 241000, China.
authors.forename: Xin
authors.initials: X
authors.lastname: Zhou
authors.affiliation: The Key Laboratory of Functional Molecular Solids, Ministry of Education, Anhui Key Laboratory of Molecule-Based Materials, School of Chemistry and Materials Science, Anhui Normal University, Wuhu, 241000, China.
authors.forename: Qinghua
authors.initials: Q
authors.lastname: Wu
authors.affiliation: The Key Laboratory of Functional Molecular Solids, Ministry of Education, Anhui Key Laboratory of Molecule-Based Materials, School of Chemistry and Materials Science, Anhui Normal University, Wuhu, 241000, China.
authors.forename: Yuanmei
authors.initials: Y
authors.lastname: Feng
authors.affiliation: The Key Laboratory of Functional Molecular Solids, Ministry of Education, Anhui Key Laboratory of Molecule-Based Materials, School of Chemistry and Materials Science, Anhui Normal University, Wuhu, 241000, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Yu
authors.affiliation: The Key Laboratory of Functional Molecular Solids, Ministry of Education, Anhui Key Laboratory of Molecule-Based Materials, School of Chemistry and Materials Science, Anhui Normal University, Wuhu, 241000, China.
authors.forename: Changjiang
authors.initials: C
authors.lastname: Yu
authors.affiliation: The Key Laboratory of Functional Molecular Solids, Ministry of Education, Anhui Key Laboratory of Molecule-Based Materials, School of Chemistry and Materials Science, Anhui Normal University, Wuhu, 241000, China.
authors.forename: Erhong
authors.initials: E
authors.lastname: Hao
authors.affiliation: The Key Laboratory of Functional Molecular Solids, Ministry of Education, Anhui Key Laboratory of Molecule-Based Materials, School of Chemistry and Materials Science, Anhui Normal University, Wuhu, 241000, China.
authors.forename: Yun
authors.initials: Y
authors.lastname: Wei
authors.affiliation: The Key Laboratory of Functional Molecular Solids, Ministry of Education, Anhui Key Laboratory of Molecule-Based Materials, School of Chemistry and Materials Science, Anhui Normal University, Wuhu, 241000, China.
authors.forename: Xiaolong
authors.initials: X
authors.lastname: Mu
authors.affiliation: The Key Laboratory of Functional Molecular Solids, Ministry of Education, Anhui Key Laboratory of Molecule-Based Materials, School of Chemistry and Materials Science, Anhui Normal University, Wuhu, 241000, China. jiao421@mail.ahnu.edu.cn.
authors.forename: Lijuan
authors.initials: L
authors.lastname: Jiao
keywords: BODIPY; dipyrromethene; dyes/pigments; intramolecular arylation; regioselectivity