1,2-Bis(1-phenylvinyl)benzene undergoes electron-transfer induced electrocyclization to generate an o-xylylene derivative which can be trapped or observed spectroscopically.
Efficient palladium-catalyzed vinylic C–H alkenylation and allenylation of gem-disubstituted ethylenes with N-tosylhydrazones of arylalkyl and diaryl ketones were achieved to access trisubstituted 1,3-dienes and tetrasubstituted allenes, respectively. An aryl to vinyl 1,4-palladium migration/carbene insertion/β-hydride elimination sequence proceeded to switch the chemo- and regioselectivities to give
Direct observation and kinetic characterization of o-quinodimethane and its radical cation variant generated in a photoinduced electron-transfer reaction of 1,2-bis(α-styryl)benzene
conditions in acetonitrile confirmed that an o-quinodimethane radicalcation (2+, λmax = 569 nm) decayed and the corresponding neutral prototype (2, λmax = 444 nm) rose with rate constants of 5.6 and 5.9 × 105 s−1, respectively, showing the first agreement in kinetics between a reactive radicalcation intermediate intervening in chemical reaction and the corresponding neutral species formed by back electron