General procedure for N-PtBu2 directed C7 arylation of indoles
Rhodium-catalyzed, P-directed selective C7 arylation of indoles
Sci Adv, Dec 14, 2018; DOI: 10.1126/sciadv.aau6468

To a 25-ml Schlenk tube, indole substrates 1 (0.20 mmol), aryl bromides 2 (0.30 to 0.4 mmol), Rh(PPh3)3Cl (11.1 mg, 0.012 mmol), and LiOtBu (48.0 mg, 0.60 mmol) were added. The tube was purged with Ar three times, followed by the addition of anhydrous m-xylene (1.0 ml). The mixture was stirred at 80° to 150°C for 24 hours. The solution was then cooled to room temperature, and the solvent was removed under vacuum directly. The crude product was purified by column chromatography on silica gel and gave the pure products 3.