Preferential oxidative addition in Suzuki cross-coupling reactions across one fluorene unit

Org Lett. 2006 Aug 31;8(18):4039-41. doi: 10.1021/ol061476b.

Abstract

The Suzuki-type cross-coupling reaction of 2,7-dihalofluorenes with 1 equiv of arylboronic acid and Pd2(dba)3/P(t-Bu3) as a catalyst system is investigated. The exclusive formation of the diarylated coupling product demonstrates that "preferential oxidative addition" is also applicable to fluorene monomers due to a controlled intramolecular motion of the regenerated Pd(0) catalyst across the "large" distance between the 2- and the 7-position of one fluorene monomer.