Tr. Hoye et al., AN EFFICIENT AND VERSATILE SYNTHESIS OF THE BUTENOLIDE SUBUNIT OF 4-HYDROXYLATED ANNONACEOUS ACETOGENINS, Tetrahedron letters, 35(41), 1994, pp. 7517-7520
Title butenolides 2 have been synthesized by an efficient and versatil
e route that provides access to any stereoisomer by use of individual
enantiomers of the precursors 3-butyn-2-ol and terminal epoxides.