Contrasting one- and two-cation binding behavior in syn- and anti-anthraquinone bibracchial podand (BiP) mono- and dianions assessed by cyclic voltammetry and electron paramagnetic resonance spectroscopy

Novel 9,10-Bis(1,3-dithiol-2-ylidene)-9,10- dihydroanthracene Derivatives Bridged by a Crown Ether Unit at the 1,8-Positions: A New Type of Redox-switchable Hosts Undergoing Reversible Structural Changes

“…4 Despite the use of 2.5 equiv. of 4a, only a monocondensation product (5) could be obtained, suggesting the presence of a severe steric hindrance of the crown ether moiety (Scheme 2).…”

Electrochemical Detection

“…Among the first to be studied were the nitrobenzene 27 and anthraquinone 28 [30,31]. Echegoyen, Gokel, and coworkers found that the reduction of 27 in acetonitrile solution underwent a 260 mV anodic shift in the presence of Na + , and similarly the reduction of 28 in THF solution underwent a 410 mV anodic shift in the presence of Li + .…”

Synthesis and Metal Binding Properties of Anthraquinone Bridged with Coumarin

“…3,9 The anthraquinone podands can be used for electrochemically switched cation transport in bulk organic membranes 7b and both monoanion and dianion species can be formed and detected. 10 Both oneelectron and two-electron reduction can lead to enhanced cation binding in anthraquinone-derived podands and lariat ethers. 7a Anthraquinones differ significantly from the nitroaromatic systems in their ability to undergo discrete one or two electron reduction and also anthraquinone substituted podands exhibit surprising geometrical effects during the electrochemical switching process.…”

“…7b Gokel and co-workers 10 have reported two armed podands based on the anthraquinone ring systems, which showed the cation binding enhancement by cyclic voltammetry. 1,8-Anthraquinone derived crown ether having a total of six oxygen donors in the macrocycling is an exceptionally strong cation binder not only when reduced, but in its neutral form as well.…”