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
Applications of triphenylpyrylium salt-sensitized electron-transfer photo-oxygenation reactions to the synthesis of benzo-fused 1,4-diaryl-2,3-dioxabicyclo[2.2.2]octanes as new antimalarial cyclic peroxides
Abstract Benzo-fused 1,4-diaryl-2,3-dioxabicyclo[2.2.2]octanes 4a–d (4a: Ar = C6H5, 4b: Ar = p-FC6H4, 4c: Ar = p-MeC6H4, 4d: Ar = p-MeOC6H4) were synthesized by 2,4,6-triphenylpyryliumtetrafluoroborate (TPPBF4)-sensitized photoinduced electron-transfer (PET)-promoted oxygenation reactions, and their in-vitro antimalarial activity was evaluated. The results showed that these substances have sufficiently high
摘要 苯并稠合的1,4-二芳基-2,3-二氧杂双环[2.2.2]辛烷4A - d(图4a:氩= C 6 H ^ 5,图4b:Ar为 p -FC 6 ħ 4,图4c:Ar为 p -的MeC 6 ħ 4,4D:Ar为 p -MeOC 6 ħ 4)由2,4,6-三苯基吡喃鎓四氟硼酸盐合成(TPPBF 4敏化的光诱导电子转移(PET)促进了氧化反应,并评估了其体外抗疟活性。结果表明,这些物质具有足够高的活性,使其能够用作抗疟铅化合物。此外,TPPPF 4-联苯共增敏PET氧合被证明是在抗疟疾环状过氧化物的构建中引入O-O部分的有效方法。 图形概要 通过TPPPF 4敏化的光诱导电子转移加氧反应合成了新的抗疟疾双环过氧化物4。