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Synthesis of CF3-containing 3,3'-cyclopropyl spirooxindoles by sequential [3 + 2] cycloaddition/ring contraction of ylideneoxindoles with 2,2,2-trifluorodiazoethane. | LitMetric

A [3 + 2] cycloaddition/ring contraction sequence of ylideneoxindoles with in situ-generated 2,2,2-trifluorodiazoethane without the use of any transition-metal catalyst has been developed. The reaction provides efficient access to biologically important and synthetically useful CF3-containing 3,3'-cyclopropyl spirooxindoles in high yield (74-99%) with high diastereoselectivity (>95:5 d.r.).

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Source
http://dx.doi.org/10.1021/jo500019aDOI Listing

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