Cooperative palladium/isothiourea catalyzed enantioselective formal (3+2) cycloaddition of vinylcyclopropanes and α,β-unsaturated esters

Jacqueline Bitai, Alastair Nimmo, Alexandra M. Z. Slawin, Andrew D. Smith*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

23 Citations (Scopus)
10 Downloads (Pure)

Abstract

A protocol for the enantioselective synthesis of substituted vinylcyclopentanes has been realised using cooperative palladium and isothiourea catalysis. Treatment of vinylcyclopropanes with Pd(PPh3)4 generates a zwitterionic π-allyl palladium intermediate that intercepts a catalytically generated α,β-unsaturated acyl ammonium species prepared from the corresponding α,β-unsaturated para-nitrophenyl ester and the isothiourea (R)-BTM. Intermolecular formal (3+2) cycloaddition between these reactive intermediates generates functionalised cyclopentanes in generally good yields and excellent diastereo- and enantiocontrol (up to >95 : 5 dr, 97 : 3 er), with the use of LiCl as an additive proving essential for optimal stereocontrol. To the best of our knowledge a dual transition metal/organocatalytic process involving α,β-unsaturated acyl ammonium intermediates has not been demonstrated previously.
Original languageEnglish
Article numbere202202621
Number of pages9
JournalAngewandte Chemie International Edition
Volume61
Issue number25
Early online date28 Apr 2022
DOIs
Publication statusPublished - 20 Jun 2022

Keywords

  • α,β-unsaturated acyl ammonium
  • Palladium catalysis
  • Isothiourea
  • Cycloaddition
  • Cooperative catalysis

Fingerprint

Dive into the research topics of 'Cooperative palladium/isothiourea catalyzed enantioselective formal (3+2) cycloaddition of vinylcyclopropanes and α,β-unsaturated esters'. Together they form a unique fingerprint.

Cite this