A new and effective route to (±)-botryodiplodin and (±)-epi-botryodiplodin acetates using a halogen atom transfer Ueno-Stork cyclization

(+/-)-Botryodiplodin and (+/-)-epi-botryodiplodin acetates were prepared in good yields following a practical four step route. The method, for the construction of the strategic tetrahydrofuran ring, hinged on an unprecedented halogen atom transfer Ueno-Stork cyclization of an O-allyl alpha,alpha-dihalohemiacetal acetate, catalyzed by the redox complex CuCl/N,N,N ',N '',N ''-pentamethyldiethylenetriamine. (c) 2006 Elsevier Ltd. All rights reserved.