Multiple-Electron Transfer in a Single Step. Design and Synthesis of Highly Charged Cation-Radical Salts

Abstract

[structure: see text]. Macromolecules 1c and 2c bearing multiple redox-active sites are synthesized by an efficient palladium-catalyzed coupling of 2,5-dimethoxytolylmagnesium bromide with readily available hexakis(4-bromophenyl)benzene and tetrakis(4-bromophenyl)methane. These macromolecular electron donors undergo reversible oxidation at a constant potential of 1.15 V vs SCE to yield robust, multiply charged cation radicals that are isolated in pure form using SbCl(5) as an oxidant. These nanometer-size cation-radical salts are shown to act as efficient "electron sponges" toward a variety of electron donors.

Organische gemischtvalente Verbindungen: ein Spielplatz für Elektronen und Löcher

“…Rathore et al [292,293] synthetisierten ebenfalls Hexaarylbenzol-Systeme, allerdings mit 2,5-Dimethoxy-4-methyl-(223) oder Triphenylvinyl-Redoxzentren (224, Schema 79).…”

Symmetric Six-Fold Arrays of Photo- and Electrochromic Dithienylethene Switches

“…30 Thus, the redox waves observed for 1c and 2c can be assigned to simultaneous multiple electron transfer 31 to produce highly charged stable species. Here we have described the synthesis and spectroscopic and electrochemical characterization of C 6 -symmetric star-shaped hexa(dithienylethene)-substituted hexaphenylbenzenes 1 and 2 prepared using a simple cobalt-catalyzed cyclotrimerization.…”

Enhanced π Conjugation around a Porphyrin[6] Nanoring

“…A variety of belt-shaped porphyrin arrays have been synthesized; [4] however, the vast majority of them lacks a complete pconjugation pathway around the whole macrocycle. Recently we reported the synthesis of a belt-shaped D 8h symmetric porphyrin[8] nanoring on an octadentate template.[5] Herein we present an efficient synthesis of an even more strained p conjugated D 6h porphyrin [6] nanoring 1, by template-directed trimerization of a porphyrin dimer 2 on a hexapyridyl template 3 (Scheme 1). This route is more direct than the synthesis of the cyclic octamer since both starting materials, 2 and 3, are readily accessible.…”