Bifunctional Brønsted Base Catalyst Enables Regio-, Diastereo-, and Enantioselective C<sub>α</sub>-Alkylation of β-Tetralones and Related Aromatic-Ring-Fused Cycloalkanones
The catalyticasymmetric synthesis of both α‐substituted and α,α‐disubstituted (quaternary) β‐tetralones through direct α‐functionalization of the corresponding β‐tetralone precursor remains elusive. A designed Brønsted base‐squaramide bifunctionalcatalyst promotes the conjugate addition of either unsubstituted or α‐monosubstituted β‐tetralones to nitroalkenes. Under these reaction conditions, not