Phosphine-mediated highly enantioselective spirocyclization with ketimines as substrates

Xiaoyu Han, Wai Lun Chan, Weijun Yao, Yongjiang Wang, Yixin Lu

Research output: Journal article publicationJournal articleAcademic researchpeer-review

116 Citations (Scopus)

Abstract

Phosphine-catalyzed enantioselective annulation reactions involving ketimines are a daunting synthetic challenge owing to the intrinsic low reactivity of ketimine substrates. A highly enantioselective [3+2] cycloaddition reaction that makes use of isatin-derived ketimines as reaction partners was developed. Notably, both simple and γ-substituted allenoates could be utilized, and various 3,2′-pyrrolidinyl spirooxindoles with a tetrasubstituted stereocenter were obtained in excellent yields and with nearly perfect enantioselectivity (>98 % ee in all cases). Like a circle in a spiral: A highly enantioselective [3+2] cycloaddition reaction that makes use of isatin-derived ketimines as reaction partners has been developed. Both simple and γ-substituted allenoates could be utilized, and various 3,2′-pyrrolidinyl spirooxindoles with a tetrasubstituted stereocenter were obtained in excellent yields and with nearly perfect enantioselectivity (>98 % ee in all cases).

Original languageEnglish
Pages (from-to)6492-6496
Number of pages5
JournalAngewandte Chemie - International Edition
Volume55
Issue number22
DOIs
Publication statusPublished - 23 May 2016
Externally publishedYes

Keywords

  • acyclic ketimines
  • amino acids
  • phosphine catalysts
  • spirooxindoles
  • [3+2] cycloaddition

ASJC Scopus subject areas

  • Catalysis
  • Chemistry(all)

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