Asymmetric [3+ 2] cycloaddition of donor–acceptor aziridines with aldehydes via carbon–carbon bond cleavage
نویسندگان
چکیده
An enantioselective [3 + 2] annulation of donor–acceptor aziridines with aldehydes has been realized using a Nd(OTf)3/N,N0-dioxide/LiNTf2 catalyst system, providing various chiral cis-1,3-oxazolidines inmoderate to good yields with high levels of stereocontrol. A relay catalytic process is proposed where LiNTf2 promotes the formation of azomethine ylide intermediates, and a chiral Nd(III)–N,N0-dioxide complex accelerates the asymmetric cycloaddition.
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