Syntheses through cascade dimerization
Posted by naturalproductman on August 30, 2012
Andrew Lawrence and co-workers at Australian National University have reported in Organic Letters on the syntheses of some polycyclic natural products, incarviditone and incarvilleatone.
milkshake said
examples of masterful biomimetic synthetic design like this one bring back the excitement I once felt about total synthesis. Please note that if the monomeric spiro intermediate could be made or resolved in optically pure form , only the desired (revised) compound would form without the isomer
naturalproductman said
Right – in other words if the monomeric rengyolone (compound 2 in the paper, although I don’t think this has a spirocyclic center) can be synthesized asymmetrically through maybe an intramolecular asymmetric oxy-Michal addition, the final dimerized product would be one enantiomer. I guess the challenge is to be able to synthesize rengyolone enantioselectively. I don’t know if this matters: but I think compounds can crystallize better when they are racemic.