Synthetic approach to pondaplin and highly strained ansa macrolides: The dramatic influence of a fluorine atom on the efficiency of ring-closing metathesis
Abstract Ring-closing metathesis has been applied to the synthesis of extremely rigid 13 to 16 membered ring lactones starting from alkenyl p-(O-allyl) cinnamates and p-(O-allyl) dihydrocinnamates. The core structure of pondaplin, a natural ansa macrolide has been prepared starting from a fluoro derivative. The presence of this atom seems to have a crucial role on the success of the RCM.