Triptycene Boronates, Boranes, and Boron Ate-Complexes: Toward Sterically Hindered Triarylboranes and Trifluoroborates

Abstract

We developed two synthetic strategies towards triptycene-derived bulky boranes, boronates, and boron ate-complexes. Starting from borylated or brominated anthracenes and using a Br/Li exchange and [4+2] cycloaddition reaction with in-situ generated benzyne, we produced a series of triptycene boronates and borates with various boron substituents in positions 1 and 9, such as BPin, Bneo, BF3K and B(Mes)2. Single-crystal X-ray diffraction analysis and UV-Vis/photoluminescence measurements provided quantitative information on the effect of the triptycene scaffold on the photophysical and electronic properties of the obtained compounds.