Novel concepts in directed biaryl synthesis - Part 76 - First synthesis of mastigophorenes A and B, by biomimetic oxidative coupling of herbertenediol

The first synthesis of mastigophorenes A and B by oxidative phenolic coupling of partially protected derivatives of their joint natural monomeric half, herbertenediol, is described. The synthesis starts from this diol itself or from the corresponding aldehyde, both available by isolation from the liverwort, Herbertus aduncus. After transformation of herbertenediol to a chemically appropriate monophenolic coupling precursor, the oxidative dehydrodimerization was brought about using (tert-BuO)(2), followed by deprotection to give mastigophorenes A and B in their 'natural' atropisomeric ratio, as isolated from the liverwort. (C) 1998 Elsevier Science Ltd. All rights reserved.