Construction of 3,4-Dihydroisoquinolinones and Indanones via DTBP-Promoted Oxidative Coupling of N‑Allylbenzamides with Aromatic Aldehydes

A metal-free oxidative tandem coupling of N-allylbenzamide with aryl aldehydes was realized. This method allowed the 1,2-difunctionalization of the CC double bond in N-allylbenzamides through simultaneous formation of two C­(sp²)–C­(sp³) bonds. In the presence of DTBP, 4-substituted 3,4-dihydroisoquinolin-1­(2H)-ones were obtained in satisfactory isolated yields. 3-Substituted indanones could also be formed by varying the structures of the starting materials.