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Single boryl isomerization in silyl-bridged photochromic diboryl dyes
Stephen K Murphy1, Chul Baik, Jia-Sheng Lu
1Department of Chemistry, Queen's University, 90 Bader Lane, K7L 3N6, Kingston, Ontario, Canada.
Abstract:
Silyl-bridged dimers of a ppy-BMes(2) (ppy = 2-phenylpyridine, Mes = mesityl) photochrome were found to undergo photochromic switching involving a single boryl unit only. A through-space intramolecular energy transfer was found to be responsible for the single-chromophore isomerization phenomenon and fluorescence quenching. Steric congestion in the diboryl molecules was found to have an impact on photoisomerization quantum efficiency.
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