The annulation of palladacycles with ortho-substituted haloarenes via C-H activation represents an efficient strategy for constructing cyclic compounds. However, low regioselectivity in such reactions has limited their broader application in organic synthesis. Herein, we report a palladium-catalyzed, regioselective cross-coupling reaction of 1-(2-iodophenyl)-1H-pyrroles with 2-chlorobenzoic acids. Using P(2,6-(OMe)2-Ph)3 as a ligand, palladacycles generated via C-H activation undergo dual cross-coupling with 2-chlorobenzoic acids with excellent regioselectivity, affording pyrrolo1,2-fphenanthridine products. This method provides convenient access to a diverse range of pyrrolo1,2-fphenanthridine derivatives.
Zuo et al. (Sat,) studied this question.