Intramolecular Ir(I)-catalyzed benzylic C-H bond amination of ortho-substituted aryl azides

Iridium(I) catalyzes the intramolecular benzylic C-H bond amination of ortho-homobenzyl-substituted aryl azides to produce indolines at 25 degrees C.

Examination of the mechanism of Rh(2)(II)-catalyzed carbazole formation using intramolecular competition experiments

The use of a rhodium(II) carboxylate catalyst enables the mild and stereoselective formation of carbazoles from biaryl azides. Intramolecular competition experiments of triaryl azides suggested the source of the selectivity. A primary intramolecular kinetic isotope effect was not observed, and correlation of the product ratios with Hammett sigma(+) values produced a plot with two intersecting lines with opposite rho values. These data suggest that electronic donation by the biaryl pi-system accelerates the formation of rhodium nitrenoid and that C-N bond formation occurs through a 4pi-electron-5-atom electrocyclization.

Rh(2)(II)-catalyzed synthesis of carbazoles from biaryl azides

An array of carbazoles (23 examples) can be synthesized from substituted biaryl azides at 60 degrees C using substoichiometric quantities of Rh(2)(O(2)CC(3)F(7))(4) or Rh(2)(O(2)CC(7)H(15))(4).