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Published on: June 10, 2021
Synthesis, Structure, and Photophysical Studies of a Pair of Novel Rigid Bichromophoric Systems Bearing a Methyl
Donald C. Craig1, Kenneth P. Ghiggino, Katrina A. Jolliffe
1School of Chemistry, University of New South Wales, Sydney, New South Wales, 2052 Australia, and School of Chemistry, University of Melbourne, Melbourne, Victoria 3052, Australia.
Abstract:
The rigid bichromophoric systems7a.2BF(4) and7b.2BF(4), comprising either a dimethoxybenzene (a) or dimethoxynaphthalene (b) unit, each covalently linked through a six-bond norbornylogous bridge to a methyl viologen unit, were synthesized with a view to studying long-range intramolecular energy (EnT) and/or electron (ET) transfer. X-ray crystallography has been used to illustrate that 7b.2BF(4) has the ability to undergo self-organization on crystallization to form extended linear arrays within the crystal lattice. Preliminary photophysical studies on 7b.2BF(4) indicate the presence of an additional rapid nonradiative process (rate constant > 2.5 x 10(10) s(-)(1)) in the bichromophore compared to a model dimethoxynaphthalene unit, and possible explanations for this process are presented.
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