The Preparation of Rigid Linear Di- (and Tri-)catechol Derivatives

The aryl-bridged rigid rod-like di- and tricatechol ligands 1-5 were prepared by aryl-aryl coupling reactions. Hereby either Suzuki coupling strategies [starting with 2,3-dimethoxyphenylboronic acid (6) as an important building block] or oxidative coupling with methyltributylammonium permanganate were used to obtain the desired compounds.