Electron transfer triplex

This latter electron transfer (Donor-Acceptor -Accepto ) triplex is reminiscent of solution phase models of energy transfer within excited triplexes (35) and of simple synthetic (D-D-A) photoinduced electron transfer systems, for example, 6,... [Pg.251]

In the following years, several groups postulated the involvement of triplexes in various photochemical electron transfer reactions [104]. [Pg.248]

This review article deals with addition and cycloaddition reactions of organic compounds via photoinduced electron transfer. Various reactive species such as exdplex, triplex, radical ion pair and free radical ions are generated via photoinduced electron transfer reactions. These reactive species have their characteristic reactivities and discrimination among these species provides selective photoreactions. The solvent and salt effects and also the effects of electron transfer sensitizers on photoinduced electron transfer reactions can be applied to the selective generation of the reactive species. Examples and mechanistic features of photoaddition and photocycloaddition reactions that proceed via the following steps are given reactions of radical cations with nucleophiles reactions of radical anions with electrophiles reactions of radical cations and radical anions with neutral radicals radical-radical coupling reactions addition and cycloaddition reactions via triplexes three-component addition reactions. [Pg.302]

Electron transfer has primarily been studied with DNA duplexes, but there are higher order structures that have been examined. Triplexes have been studied where it was shown that transfer to the third strand occurs. In quadruplex structures more damage occurs at the external tetrads, and quad-ruplex guanines are more effective traps than when in a duplex. Charge transfer has also been examined with three-way " and four-way junctions. DNA bound to electrode surfaces has been used to study the electrochemical... [Pg.759]

A triplex electron-transfer mechanism involving interaction of dibenzoylmethanatoboron difluoride (DMB) and an aromatic co-sensitizer (A — toluene, ethylbenzene, biphenyl, and durene) with N was suggested based on the results from a chemically induced dynamic nuclear polarization study of the reaction ... [Pg.344]