A highly efficient dehydrogenative reaction of a series of nucleophiles with 9-aryl-fluoren-9-ols has been realized by using only 2 mol% of Sc(OTf)3 as a catalyst. The corresponding indole-containing 9,9-diarylfluorenes were obtained in up to 99% yield as well as other electron-rich (hetero)arene adducts. The protocol exhibits high selectivity, mild reaction conditions and good substrate compatibility (32 examples). This protocol is further highlighted by its applications in the construction of potential electroluminescent materials.