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Z. Naturforsch. 2014,
69b, 541 – 553
doi:10.5560/ZNB.2014-4060
Phenothiazine-Aromatic Hydrocarbon Acceptor Dyads as Photo-induced Electron Transfer Systems by Ugi Four-Component Reaction
Heinrich-Heine Universität Düsseldorf, Institut für Organische Chemie und Makromolekulare Chemie, Universitätsstraße 1, D-40225 Düsseldorf, Germany
Reprint requests to Prof. Dr. Thomas J. J. Müller. Fax: +49 (0)211 81 14324. E-mail:
ThomasJJ.Mueller@uni-duesseldorf.de
Received March 19, 2014 / published online May 7, 2014
A phenothiazinyl donor moiety can be covalently coupled to aromatic hydrocarbon acceptor units via Ugi four-component reaction in an efficient, rapid, and highly convergent fashion. These novel phenothiazine-acceptor dyads are electronically decoupled in the electronic ground state according to UV/Vis spectroscopy and cyclic voltammetry. In the excited state the inherent acceptor luminescence is substantially quenched. Calculations of the Gibbs energy of photo-induced electron transfer from readily available UV/Vis spectroscopic and cyclovoltammetric data according to the Weller approximation rationalizes the feasibility of the reductive electron transfer from phenothiazine to the aromatic hydrocarbon upon photoexcitation.
Key words: Absorption Spectroscopy, Cyclic Voltammetry, Chromophores, Fluorescence, Multicomponent Reactions, Photo-induced Electron Transfer