Azaborahelicene fluorophores derived from four-coordinate N,C-boron chelates: synthesis, photophysical and chiroptical properties.

ABSTRACT: A series of six azaborahelicenes with varying electron-donor substitution at the 4-position of the aryl residue (i.e., naphthyl) or with variable π-extension of the aryl residue (thianthrenyl, anthryl, pyrenyl) was prepared with an efficient and flexible synthetic protocol. These different types of functionalization afforded notably pronounced intramolecular charge-transfer (ICT) character for the dyes with the strongest electron donor substitution (NMe₂) or easiest to oxidize aryl residues, as evidenced by photophysical investigations. These effects also impact the corresponding chiroptical properties of the separated M- and P-enantiomers, which notably display circularly polarized luminescence (CPL) with dissymmetry factors in the order of magnitude of 10^-4 to 10^-3. Theoretical calculations confirm the optical spectroscopy data and are in agreement with the proposed involvement of ICT processes.

SUBMITTER: Vazquez-Dominguez P 

PROVIDER: S-EPMC10825847 | biostudies-literature | 2024 Jan

REPOSITORIES: biostudies-literature