Direct β‑Alkylation of Ketones and Aldehydes via Pd-Catalyzed Redox Cascade

We
report a direct β-alkylation of ketones and aldehydes
with simple alkyl bromides through a Pd-catalyzed redox-cascade strategy.
The use of a Cu cocatalyst is important for improved efficiency. The
reaction is redox-neutral, without the need for strong acids or bases.
Both cyclic and acyclic ketones, as well as α-branched aldehydes,
are suitable substrates for coupling with secondary and tertiary alkyl
bromides. Concise formal synthesis of Zanapezil is achieved using
this β-alkylation method.