Title
Significant Enhancement of Absorption and Luminescence Dissymmetry Factors in the Far‐red Region: Zinc(II) Homoleptic Helicate Formed by a Pair of Achiral Dipyrromethene Ligands
Author
Hiroaki Ito, Hayato Sakai, Yoshinori Okayasu, Junpei Yuasa, Tadashi Mori, Taku Hasobe
Year
2018
Journal
Chemistry A European Journal
Abstract
A homoleptic zinc(II) helicate organized by a pair of achiral dipyrromethene ligands through zinc(II)‐coordination were synthesized to evaluate the chiroptical properties. This zinc complex afforded strong exciton‐coupled chiroptical responses from the helical configuration with a strong absorption dissymmetry factor |gabs| (up to 0.20). More importantly, an intense polarized luminescence in the far‐red region (700‐850 nm) with a fluorescence quantum yield ΦFL of 0.23 was observed for this helicate with a dissymmetry factor |glum| of 0.022, the largest value among the rare earth‐ and precious metal‐free small molecules, to the best of our knowledge. These unprecedentedly large g values were supported by theoretical calculations.
Instrument
FP-8500
Keywords
Fluorescence, Quantum yield, Organic chemistry, Coordination chemistry, Optical properties