An approach involving the use of a bifunctional aminocatalyst containing Brønsted base and iminium activation sites for asymmetric multicomponent reactions involving [1,2]-phospha-Brook rearrangement has yet to be realized. Herein, we present an aminocatalytic enantioselective conjugate addition of α-phosphonyloxy enolates formed [1,2]-phospha-Brook rearrangement to α,β-unsaturated ketones. The methodology unfolds a simple one-pot operation consisting of a robust additive-free catalytic system providing a series of oxindole derivatives having two contiguous stereocenters in high yields with excellent stereoselectivities.
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Graduate School of Pharmaceutical Sciences, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
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Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India.
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Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India.
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