Near infra-red dyes based on pyrene aza-BODIPYs. (20th March 2018)

• Record Type: Journal Article
• Authors: Balsukuri, Naresh; Boruah, Nayan Jyoti; Kesavan, Praseetha E.; Gupta, Iti
• Is Part Of: New journal of chemistry. Volume 42:Number 8(2018)
• Page Start: 5875
• Page End: 5888
• Publication Date: 2018-03-20
• Subjects: Chemistry -- Periodicals; Chimie -- Périodiques; 540
• DOI: 10.1039/c7nj03408c
• Languages: English
• ISSNs: 1144-0546

Abstract

Abstract : Donor–acceptor type pyrene substituted aza-BODIPYs are reported, and efficient energy transfer from pyrene moieties to the aza-BODIPY core caused significant red shifts in their absorption and emission spectra. Abstract : Pyrene substituted donor–acceptor type NIR aza-BODIPYs were designed and synthesized. The 1, 7-positions of the aza-BODIPY core were substituted by pyrene moieties and the 3, 5-positions were substituted with phenyl/2-thienyl or anisyl groups in the aza-BODIPYs. The effect of substituents on their photophysical and electrochemical properties was studied; also, computational studies were carried out for the target aza-BODIPYs. These near infrared dyes displayed the lowest energy absorption maxima in the range of 670–738 nm; whereas, their emission maxima were centered on ≈764 nm. The absorption and emission spectra of the aza-BODIPYs were significantly red shifted (72–94 nm) as compared to the parent tetra-phenylaza-BODIPY. Fluorescence studies suggested effective energy transfer (up to 65%) from donor groups to the aza-BODIPY core in all the compounds. TD-DFT studies indicated significant electronic interactions between energy donor groups and the aza-BODIPY core in all the aza-BODIPYs. The values of HOMO–LUMO gap (Δ E ) calculated from cyclic voltammetry data were comparable with those obtained from DFT studies.