Diaryliodonium Salt-Mediated Intramolecular C-N Bond Formation Using Boron-Masking N-Hydroxyamides.

Intramolecular aromatic C-N bond formation reactions using electron-rich aromatic tethered boron-masking N-hydroxyamide as substrate were realized. These new C-N bond formation reactions involve the in situ generation of a diaryliodonium salt by treatment with hypervalent iodine, deborylation by base treatment, spontaneous N → O acyl migration, cyclization, reductive elimination, elimination of benzoic acid, and tautomerization to indole formation. Hereby, we obtained highly functionalized electron-rich indoles and quinoline in practical yields.