Total Synthesis of Linear Polyprenoids. 2. Improved preparation of the Aromatic Nucleus of Ubiquinone

Article abstract of DOI:10.1021/jo00226a028

Highly efficient copper-catalyzed polymethoxylation of tribromocresol is the key process in a three-step, practical approach to obtain ubiquinone 0 from p-cresol.Short syntheses of several ubiquinones were achieved via direct, copper-mediated coupling of 2-lithio-3,4,5,6-tetramethoxytoluene to the appropriate polyprenyl bromide.