Selective synthesis and optical properties of diimidazo[1, 2-a:5′, 1′-c]quinoxaline derivatives. Issue 26 (28th June 2019)

• Record Type: Journal Article
• Authors: Matsumoto, Shoji; Abe, Shunsuke; Akazome, Motohiro
• Is Part Of: Tetrahedron. Volume 75:Issue 26(2019)
• Page Start: 3657
• Page End: 3665
• Publication Date: 2019-06-28
• Subjects: Diimidazo[1, 2-a:5′, 1′-c]quinoxaline -- Coupling reaction -- Structural isomer -- Fluorescence -- Electron-donating character; Chemistry, Organic -- Periodicals; 547.005
• DOI: 10.1016/j.tet.2019.05.041
• Languages: English
• ISSNs: 0040-4020

Abstract

Abstract: Novel diimidazo[1, 2- a :5′, 1′- c ]quinoxaline derivatives were synthesized by a Pd-catalyzed intramolecular coupling reaction of 1, 2-bis(2-iodo-1 H -imidazol-1-yl)benzene. This method was applied to the selective introduction of an aryl substituent at the 10 position by the addition of a boronic ester. Moreover, a stepwise introduction of the aryl substituent could be achieved by the further coupling reaction at the 3 position. Focused on the optical properties, a more efficient substituent effect at the 10 position was obtained compared with the analogous structure, diimidazo[1, 2- a :2′, 1′- c ]quinoxaline derivatives. In addition, we revealed that the diimidazo[1, 2- a :5′, 1′- c ]quinoxaline skeleton potentially has an electron-donating character on the optical properties by introducing an electron-withdrawing substituent. Graphical abstract: Image 1