Unexpectedly Superior Efficiency of Chloride-directed Double Suzuki-Miyaura Cross-coupling Reaction to That of Bromide for the Synthesis of Sterically Hindered 2,7-Diaryl Fluorenes

Sterically hindered 2,7-diaryl fluorenes have been efficiently synthesized via double Suzuki–Miyaura cross-coupling reactions of challenging 2,7-dichlorofluorene with multiple di- ortho -substituted arylboronic acids using the NHC–Pd catalyst INPd.