SYNTHESIS-STUTTGART, sa.10, ss.1619-1624, 2005 (SCI-Expanded)
The syntheses of N-hcxylcarbazol-2-yl- and -3-yl-boronic acids (1 and 2) are described on a ca. 7 g scale, starting from commercially available 2,5-dibromonitrobenzene (4) and carbazole (11), respectively. Compounds I and 2 underwent efficient palladium-catalyzed cross-coupling reactions under Suzuki-Miyaura conditions to yield products 17, 18 and 20. Compound 18 reacted with IrCl3 to give the tris-cyclometalated (pyridin-2-yl)carbazole iridium(III) complex 21, the X-ray crystal structure of which is reported.