Rhodium(I)-catalyzed addition of phenols to dienes. A new convergent synthesis of vitamin E

A highly convergent and atom-economical synthesis of (dl)-[α]-tocopherol (vitamin E) is proposed, the realization of which was made possible by the discovery of the regioselective Rh(I)-catalyzed arylation of β-springene with trimethylhydroquinone. Other phenolic compounds and 2-substituted-1,3-dienes were shown to undergo this transformation.