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Enantioselective dearomative [3+2] annulation of 5-amino-isoxazoles with quinone monoimines. | LitMetric

The first enantioselective dearomative [3+2] annulation of 5-amino-isoxazoles with quinone monoimines was realized using a chiral phosphoric acid as catalyst. Various novel (bridged) isoxazoline fused dihydrobenzofurans bearing two continuous quaternary stereocenters were achieved in moderate to good yields (up to 94%) with moderate to good enantioselectivities (up to 98% ee). The absolute configurations of two products were assigned by X-ray crystal structural analyses and a plausible reaction mechanism was proposed.

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http://dx.doi.org/10.1039/d0cc05807fDOI Listing

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