A model framework related to the calcheamicin family of enediyne toxins was evaluated in its reactivity toward cycloaromatization through the arene 1,4-diyl intermediates and hydrogen atom abstractions. The keto version 9 is relatively unreactive, with t1/2 = 1.5 h at 60°C. The product from hydride reduction of the ketone, alcohol 13b, is much more reactive, with t1/2 = 50 min at 0°C. In both cases, the rate of rearrangement is independent of the hydrogen atom donor, consistent with a rate-determining first step (cyclization).
All Science Journal Classification (ASJC) codes
- Physical and Theoretical Chemistry
- Organic Chemistry
- Arene diradical
- Enediyne model
- Hydrogen atom abstraction