Rh(III)-catalyzed regioselective C(sp)-H alkenylation of isoquinolones with methoxyallene: A facile access to aldehyde-bearing isoquinolones.

A simple and rapid access to isoquinolone aldehyde scaffolds has been established by a rhodium-catalyzed reaction between isoquinolone and methoxyallene that forges alkenylation in an explicit regioselective manner. Herein, methoxyallene serving as an acrolein equivalent results in execution of this unique functionalization. Furthermore, the compatibility with complex molecules underscores the significance of this developed protocol. The mechanistic proposal for this regioselective transformation was consistent with kinetic studies and several control reactions.