A convergent approach to the totalsynthesis of pteridicacid A, having potent plant growth regulator activity, is described. Key steps include the desymmetrization of bicyclic olefin with Brown’s chiral hydroboration, acid-mediated spiroketalization, and zirconium-catalyzed ethylmagnesation protocol to install the ethyl stereocenter at C14.
The synthesis of the C1–C15 fragment of elaiolide was achieved by successfully utilizing the desymmetrization strategy, zirconium catalyzed C–C bond formation and doublestereodifferentiatingaldol reactions.