Palladium-Catalyzed sp3 C–H Benzoxylation of Alanine Derivatives Using Aldehydes under Ambient Conditions

Pd(II)-Catalyzed sp3 C-H bond benzoxylation of N-phthaloyl alanine derivatives possessing an 8-aminoquinolyl group as a directing group with aldehydes under ambient conditions is reported. When a solution of an alanine derivative and an aldehyde in a toluene/water co-solvent was reacted in the presence of palladium catalyst and tert-butyl hydroperoxide at room temperature, a benzoxylated product was formed in up to 68% yield. The protecting group of the obtained benzoxylated product was smoothly removed to afford a free amide in high yield.