title: Synthesis, Structure, and Optical Studies of Donor-Acceptor-Type Near-Infrared (NIR) Aza-Boron-Dipyrromethene (BODIPY) Dyes.
abstract: Six donor-acceptor-type near-infrared (NIR) aza-boron-dipyrromethene (BODIPY) dyes and their corresponding aza-dipyrrins were designed and synthesized. The donor moieties at the 1,7-positions of the aza-BODIPY core were varied from naphthyl to N-phenylcarbazole to N-butylcarbazole. The 3,5-positions were also substituted with phenyl or thienyl groups in the aza-BODIPYs. Photophysical, electrochemical, and computational studies were carried out. The absorption and emission spectra of aza-BODIPYs were significantly redshifted (≈100 nm) relative to the parent tetraphenylaza-BODIPY. Fluorescence studies suggested effective energy transfer (up to 93 %) from donor groups to the aza-BODIPY core in all of the compounds under study. Time-dependent (TD)-DFT studies indicated effective electronic interactions between energy donor groups and aza-dipyrrin unit in all the aza-BODIPYs studied. The HOMO-LUMO gap (ΔE) calculated from cyclic voltammetry data was found to be lower for six aza-BODIPYs relative to their corresponding aza-dipyrrins.
authors.affiliation: Indian Institute of Technology Gandhinagar, Village Palaj, Simkheda, Gandhinagar, Gujarat-, 382355, India.
authors.forename: Naresh
authors.initials: N
authors.lastname: Balsukuri
authors.affiliation: School of Chemical Sciences, Central University of Gujarat, Gandhinagar, Gujarat, India.
authors.forename: Mohsin Y
authors.initials: MY
authors.lastname: Lone
authors.affiliation: School of Chemical Sciences, Central University of Gujarat, Gandhinagar, Gujarat, India.
authors.forename: Prakash C
authors.initials: PC
authors.lastname: Jha
authors.affiliation: Integrated Centre for Sciences, Ehime University, Matsuyama, 790-8577, Japan.
authors.forename: Shigeki
authors.initials: S
authors.lastname: Mori
authors.affiliation: Indian Institute of Technology Gandhinagar, Village Palaj, Simkheda, Gandhinagar, Gujarat-, 382355, India. iti@iitgn.ac.in.
authors.forename: Iti
authors.initials: I
authors.lastname: Gupta
mesh_terms: D001896:Boron Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D055664:Electrochemical Techniques; D004735:Energy Transfer; D005453:Fluorescence; D005456:Fluorescent Dyes / Q000138:chemical synthesis / Q000737:chemistry*; D008027:Light; D008956:Models, Chemical; D010084:Oxidation-Reduction; D011758:Pyrroles / Q000138:chemical synthesis / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D001896:Boron Compounds; D005456:Fluorescent Dyes; D011758:Pyrroles
keywords: X-ray diffraction; density functional calculations; donor-acceptor systems; dyes/pigments; energy transfer