“…Alkylation at the 9-position of the fluorene ring can be easily carried out utilizing the acidity of the hydrogens at the 9-position, 5,6,9,[13][14][15][16]21 and introduction of substituents at 2-or 7-position was also effectively accomplished by electrophillic substitution of the fluorene ring. 5,9,[12][13][14][15]21 Further manipulation at 2-or 7-position has been carried out by standard procedures starting from the appropriate fluorene compounds having diversely transformable substituents such as nitro and/or halogen group. In particular, various metal-catalyzed coupling reactions of bromo-or iodo-fluorenes with stannyl compounds (Stille reaction), 1,9 alkenes (Heck reaction), [1][2][3]5,6,15,16 arylboronic acid (Suzuki reaction), 10,18,21 terminal alkynes (Sonogashira reaction), 10 or amines (Buchwald-Hartwig or Ullmann reaction) 5,9,16 provided a variety of alkenyl-, aryl-, alkynyl-, or amino-substituted fluorene derivatives.…”