Flow-Assisted Synthesis of Alkyl Citrate Natural Products

J Org Chem. 2021 Oct 15;86(20):14223-14231. doi: 10.1021/acs.joc.1c01645. Epub 2021 Oct 6.

Abstract

The development of a flow-assisted synthesis of alkyl citrate natural products is described. The flow route harnesses a number of steps including the generation of ketene silyl acetal, a formal [2 + 2] cycloaddition, and a methanolysis cascade to efficiently generate a highly substituted, and stereodefined tetrahydrofuran intermediate. A heterogeneous pseudo-Finkelstein reaction and zinc-mediated elimination furnish a key alkene alkyl citrate fragment in high yield over a multistep sequence that provides direct entry to compounds such as (-)-CJ-13982 (1), (-)-CJ-13,981 (2), L-731,120 (3), and related natural products. The flow methodology developed in this study enables a new machine-assisted approach toward the efficient and scalable synthesis of the alkyl citrate family of natural products.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acetals
  • Biological Products*
  • Citrates
  • Citric Acid
  • Cycloaddition Reaction

Substances

  • Acetals
  • Biological Products
  • Citrates
  • Citric Acid