Transamination of Zwitterionic Quinones with Polyamines: The Carbon Bridge Matters.

The one-pot transamination reactions on a zwitterionic benzoquinonemonoimine yield either a quinoxaline derivative or bis-zwitterionic macrocycles, depending on the number of carbon atoms bridging primary polyamines. These latter products, featuring two confined donor cavities, are the result of a [2 + 2] condensation without the need for template effect or high dilution conditions.