Expedient total syntheses of rhein and diacerhein via fries rearrangement
Short and practical total syntheses of rhein (1) and diacerhein (2) have been achieved via a Fries rearrangement and bis-carbonylation strategy followed by cyclization in molten salt, starting from dibromoester 7.
Tisserand, Steve,Baati, Rachid,Nicolas, Marc,Mioskowski, Charles