Intramolecular H-Bonds in an Organocatalyst Enabled an Asymmetric Michael/Alkylation Cascade Reaction to Construct Spirooxindoles Incorporating a Densely Substituted Cyclopropane Motif

Org Lett. 2022 Nov 25;24(46):8553-8558. doi: 10.1021/acs.orglett.2c03578. Epub 2022 Nov 15.

Abstract

A cascade Michael addition/alkylation reaction between 3-chlorooxindoles and α-cyano chalcones catalyzed using a multifunctional quinine-derived aminoindanol-thiourea substance was investigated. A series of spirooxindoles incorporating a densely substituted cyclopropane motif were efficiently obtained with moderate to excellent diastereo- and enantioselectivity and further transformed to products with versatile structural diversity. Density functional theory (DFT) calculations indicated that the tentative intramolecular hydrogen bonds in the chiral catalyst were crucial for the stereocontrol.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alkylation
  • Cyclopropanes*
  • Stereoisomerism
  • Thiourea* / chemistry

Substances

  • cyclopropane
  • Cyclopropanes
  • Thiourea