Publications by authors named "Joao V Schober"
We present a six-step cascade that converts 1,3-distyrylbenzenes (-stilbenes) into nonsymmetric pyrenes in 40-60% yields. This sequence merges photochemical steps, ,-alkene isomerization, a 6π photochemical electrocyclization (Mallory photocyclization); the new bay region cyclization, with two radical iodine-mediated aromatization steps; and an optional aryl migration. This work illustrates how the inherent challenges of engineering excited state reactivity can be addressed by logical design.
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- The study examines how certain types of arenes (aromatic compounds) react in Diels-Alder reactions, particularly focusing on dearomatization, which is the process of losing aromatic character.
- It finds that substituted arenes and η-arenes have high energy barriers for cycloaddition, making them less reactive.
- However, once these arenes undergo significant dearomatization, they can have much lower energy barriers (around 20 kcal/mol or less) for the [4 + 2] cycloaddition, indicating enhanced reactivity.