title: Enantioselective Synthesis of Caprolactam and Enone Precursors to the Heterocyclic DEFG Ring System of Zoanthenol.
abstract: The enantioselective synthesis of both caprolactam and enone synthons for the DEFG ring system of zoanthenol are described. The evolution of this synthetic approach proceeds first through a synthesis using the chiral pool as a starting point. Challenges in protecting group strategy led to the modification of this approach beginning with (±)-glycidol. Ultimately, an efficient approach was developed by employing an asymmetric hetero-Diels-Alder reaction. The caprolactam building block can be converted by an interesting selective Grignard addition to the corresponding enone synthon. Addition of a model alkyne provides support for the late-stage addition of a hindered alkyne into the caprolactam building block.
authors.affiliation: The Arnold and Mabel Beckman Laboratory for Chemical Synthesis, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125.
authors.forename: Jeffrey T
authors.initials: JT
authors.lastname: Bagdanoff
authors.affiliation: The Arnold and Mabel Beckman Laboratory for Chemical Synthesis, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125.
authors.forename: Douglas C
authors.initials: DC
authors.lastname: Behenna
authors.affiliation: The Arnold and Mabel Beckman Laboratory for Chemical Synthesis, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125.
authors.forename: Jennifer L
authors.initials: JL
authors.lastname: Stockdill
authors.affiliation: The Arnold and Mabel Beckman Laboratory for Chemical Synthesis, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125.
authors.forename: Brian M
authors.initials: BM
authors.lastname: Stoltz
keywords: allylation; enantioselective; hetero-Diels-Alder; zoanthamines; zoanthenol