Amorphous hole-transporting carbazole dendrimers, 1,4-bis[3,6-di(carbazol-9-yl)carbazol-9-yl]-2,6-di(2-ethylhexyloxy)benze ne (G2CB) and 1,4-bis[3,6-di(carbazol-9-yl)carbazol-9-yl]-9-(2-ethylhexyl)carbazole (G2CC), were synthesized by a divergent approach involving bromination and Ullmann coupling reactions. Compounds G2CB and G2CC showed high thermal stability (T-g=206 to 245 degrees C) and excellent electrochemical reversibility. Double-layer organic light-emitting diodes were fabricated by using G2CB and G2CC as hole-tran sporting layers (HTLs) and tris (8-quinolinato)aluminum (Alq(3)) as light-emissive layer with the device configuration of indium tin oxide/HTL/Alq(3)/LiF:Al. Both devices exhibited bright green emission from Alq(3). The device using G2CC as HTL has the best performance with a maximum brightness of 8900 cd/m(2) at 14 V and a low turn-on voltage of 3.5 V. (C) 2007 Elsevier B.V. All rights reserved.