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A C₁-symmetric N-heterocyclic carbene catalysed oxidative spiroannulation of isatin-derived enals: highly enantioselective synthesis of spirooxindole δ-lactones.

ABSTRACT: A C₁-symmetric N-heterocyclic carbene (NHC)-catalysed activation of isatin-derived enals under oxidative conditions was achieved. The in situ generated α,β-unsaturated acyl azolium species was efficiently trapped by 1,3-dicarbonyl compounds via a Michael addition/spiroannualtion cascade, delivering a series of synthetically important spirooxindole δ-lactones with up to 96% enantioselectivity.

SUBMITTER: Lin JB

PROVIDER: S-EPMC9080099 | biostudies-literature | 2018 Apr

REPOSITORIES: biostudies-literature

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A C1-symmetric N-heterocyclic carbene catalysed oxidative spiroannulation of isatin-derived enals: highly enantioselective synthesis of spirooxindole δ-lactones.

Lin Jun-Bing JB Cheng Xi-Na XN Tian Xiao-Dong XD Xu Guo-Qiang GQ Luo Yong-Chun YC Xu Peng-Fei PF

RSC advances 20180424 28

A C1-symmetric N-heterocyclic carbene (NHC)-catalysed activation of isatin-derived enals under oxidative conditions was achieved. The in situ generated α,β-unsaturated acyl azolium species was efficiently trapped by 1,3-dicarbonyl compounds via a Michael addition/spiroannualtion cascade, delivering a series of synthetically important spirooxindole δ-lactones with up to 96% enantioselectivity. ...[more]

PMID: 35539478

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