A convergent, nine-step (LLS), enantioselective synthesis of α-cyclopiazonic acid and related natural products is reported. The route features a) an enantioselective aziridination of an imine with a chiral sulfur ylide; b) a bioinspired (3+2)-cycloaddition of the aziridine onto an alkene; and c) installation of the acetyltetramic acid by an unprecedented tandem carbonylative lactamization/N-O cleavage of a bromoisoxazole.
Keywords: (3+2)-cycloaddition; aziridination; sulfur ylide; total synthesis; α-cyclopiazonic acid.
© 2018 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.