Intramolecular Palladium(II)-Catalyzed
6-endo C–H Alkenylation Directed by the Remote N‑Protecting Group: Mechanistic Insight and Application
to
the Synthesis of Dihydroquinolines
posted on 2020-01-07, 18:04authored byAsier Carral-Menoyo, Lia Sotorríos, Verónica Ortiz-de-Elguea, Aitor Diaz-Andrés, Nuria Sotomayor, Enrique Gómez-Bengoa, Esther Lete
A protocol for the
Pd(II)-catalyzed C–H alkenylation reaction
of substituted N-allylanilines via an unusual 6-endo process has been developed. A density functional theory
(DFT) study of the mechanistic pathway has shown that the coordination
of the remote protecting group to the palladium center is determinant
for the control of the regioselectivity in favor of the 6-endo process. The reaction would proceed via prior activation
of the alkene. This procedure constitutes a mild and efficient method
for the synthesis of 1,4-dihydroquinoline derivatives from simple
and readily accessible substrates.