Tunable Synthesis of Functionalized Cyclohexa-1,3-dienes and 2‑Aminobenzophenones/Benzoate from the Cascade Reactions of Allenic Ketones/Allenoate with Amines and Enones

A TEMPO-dependent tunable synthesis
of functionalized cyclohexa-1,3-dienes
and 2-aminobenzophenones/benzoate from the one-pot cascade reactions
of allenic ketones/allenoate with amines and enones is presented.
Mechanistically, the construction of the entitled six-membered carbocycles
involves the in situ generation of an enaminone intermediate via the
conjugate addition of allenic ketone with amine followed by its catalyst-
and base-free [3+3] annulation with enone along with the simultaneous
introduction of the valuable amino and carbonyl groups.