Abstract
Upon two-electron oxidation of the title electron donor 1a, the elongated central C9-C10 bond was cleaved to give the biphenyl-2,2'-diyl bis(9-xanthenylium) dye 2a2+, which regenerated the colorless dispiro compound 1a by two-electron reduction. Presence of isosbestic points in the UV-Vis spectra during the electrochemical oxidation of 1a to 2a2+ indicates the negligible steady-state concentration of the intermediary cation radical. Interconversion between optically resolved 1a and 2a2+ is accompanied by drastic changes in CD spectra again with several isosbestic points, and racemization of (<I>P</I>),(<I>M</I>)-1a and (<I>S</I>),( <I>R</I>)-2a2+ does not occur at ambient conditions. This redox pair represents a new motif for the multi-output response system, where the electrochemical input is transduced into two independent spectral outputs.
Translated title of the contribution | Electrochiroptical Response of Dispiro[4,5-dibromo-9,10-dihydrophenanthrene-9,9':10,9'-bixanthene] Derivatives |
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Original language | Undefined/Unknown |
Pages (from-to) | 1022-1022 |
Number of pages | 1 |
Journal | 基礎有機化学討論会要旨集(基礎有機化学連合討論会予稿集) |
Volume | 16 |
Issue number | 0 |
DOIs | |
Publication status | Published - 2002 |