A Diradical Approach towards BODIPY‐Based Dyes with Intense Near‐Infrared Absorption around λ=1100 nm. Issue 8 (25th January 2016)

• Record Type: Journal Article
• Authors: Ni, Yong; Lee, Sangsu; Son, Minjung; Aratani, Naoki; Ishida, Masatoshi; Samanta, Animesh; Yamada, Hiroko; Chang, Young‐Tae; Furuta, Hiroyuki; Kim, Dongho; Wu, Jishan
• Is Part Of: Angewandte Chemie international edition. Volume 55:Issue 8(2016)
• Page Start: 2815
• Page End: 2819
• Publication Date: 2016-01-25
• Subjects: BODIPY -- dyes/pigments -- fluorescence -- radicals -- reactive oxygen species; Chemistry -- Periodicals; 540
• DOI: 10.1002/anie.201511151
• Languages: English
• ISSNs: 1433-7851

Abstract

Abstract: A diradical approach to obtain stable organic dyes with intense absorption around λ =1100 nm is reported. The para ‐ and meta ‐quinodimethane‐bridged BODIPY dimers BD‐1 and BD‐2 were synthesized and were found to have a small amount of diradical character. These molecules exhibited very intense absorption at λ =1088 nm ( ɛ =6.65×10 5 M −1 cm −1 ) and 1136 nm ( ɛ =6.44×10 5 M −1 cm −1 ), respectively, together with large two‐photon‐absorption cross‐sections. Structural isomerization induced little variation in their diradical character but distinctive differences in their physical properties. Moreover, the compounds showed a selective fluorescence turn‐on response in the presence of the hydroxyl radical but not with other reactive oxygen species. Abstract : BODIPY sees red : para ‐ and meta ‐quinodimethane‐bridged BODIPY dimers (see example) absorb strongly around λ =1100 nm and have a small amount of diradical character ( y ). The dyes were found to have large two‐photon‐absorption cross‐sections in the NIR region and showed selective fluorescence turn‐on for the hydroxyl radical over other reactive oxygen species.