Cyclometallated gold(III) complexes as effective catalysts for synthesis of propargylic amines, chiral allenes and isoxazoles

Karen Ka Yan Kung, Vanessa Kar Yan Lo, Hok Ming Ko, Gai Li Li, Pui Ying Chan, King Chi Leung, Zhongyuan Zhou, Ming Zhong Wang, Chi Ming Che, Man Kin Wong

Research output: Journal article publicationJournal articleAcademic researchpeer-review

67 Citations (Scopus)

Abstract

A series of cyclometallated gold(III) complexes [Au(CN)Cl2] 1a-l (HCN=arylpyridines) and a PEG-linked complex 1m were synthesized. Complexes 1a-m are effective in catalyzing the synthesis of propargylic amines, chiral allenes and isoxazoles. Six-membered ring cyclometallated gold(III) complexes 1f-l exhibited higher catalytic activity than five-membered ring cyclometallated gold(III) complexes 1a-e. The diastereoselectivity of propargylic amines could be tuned by using chiral aldehyde and/or amine substrates. Excellent enantioselectivities (90-98% ee) were achieved in chiral allene synthesis. Chiral allene racemization could be minimized by using 1f as catalyst. The PEG-linked catalyst 1m is the most catalytically active towards synthesis of propargylic amines, in which case a product turnover of 900 was achieved. Moreover, 1m could be repeatedly used for 12 reaction cycles, leading to an overall turnover number of 872.
Original languageEnglish
Pages (from-to)2055-2070
Number of pages16
JournalAdvanced Synthesis and Catalysis
Volume355
Issue number10
DOIs
Publication statusPublished - 8 Jul 2013

Keywords

  • allenes
  • cyclometallation
  • gold catalysis
  • isoxazoles
  • propargylic amines

ASJC Scopus subject areas

  • Catalysis
  • Organic Chemistry

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