Convergent Synthesis of Fluorene Derivatives by a Rhodium-Catalyzed Stitching Reaction/Alkene Isomerization Sequence.

A convergent synthetic method for the synthesis of fluorene derivatives has been developed by devising a rhodium-catalyzed stitching reaction/alkene isomerization sequence. The reactions proceed smoothly under mild conditions for a variety of substrate combinations, and extended π-conjugation systems are also readily accessible by utilizing this synthetic method. Optical properties of the obtained fluorene derivatives have also been examined.