Date : Friday, September 18th, 2026 10:30 am - 11:30 am Place : Seminar Room 5 (A615), 6th Floor, ISSP Lecturer : Dr. Denis Frath Affiliation : Laboratoire de Chimie - ENS Lyon Committee Chair : Takashi Hirose (ext. 63444)
e-mail: thirose@issp.u-tokyo.ac.jpLanguage in Speech : English

Constructing sophisticated luminescent dyes around a tetrahedral boron(III) centre is a particular approach that has fuelled the creativity of chemists motivated by their use as molecular probes and in photonics.[1] Among these dyes, Boranils have attracted particular interest and have been developed for energy transfer, protein labeling, or NLO imaging. We have recently described a very simple and efficient gram-scale synthetic pathway towards Boranils substituted directly on the boron center by 1,1′-bi-2-naphtol derivatives (BINOL).[2] These chiral dyes typically feature high molar absorption coefficient in the range of 35,000 to 90,000 M-1.cm-1, absorption dissymmetry factor (gabs) in the range of 2.5–5.5 x 10-4 at the maximum wavelength of absorption of Boranils and Circularly Polarized Luminescence (CPL) brightness up to BCPL = 5.4 M-1.cm-1. Based on this new family of CPL emitters, we are currently developing supramolecular chiral soft-materials such as stimuli-responsive gels and liquid crystals.[3],[4] As an illustration, we have developed molecular switches taking advantage of the control of energy transfer to a photochromic diarylethene (DAE) core to modulate chiroptical properties in liquid crystals thin films with enhanced gabs and glum.[5]