An asymmetric Mannich reaction has been developed to generate chiral β-amino esters in good yields with excellent enantiomeric excesses (ee, up to 99%) using a chiral bifunctional thiourea catalyst derived from (,)-cyclohexyldiamine. This is the first report on the addition of 3-indolinone-2-carboxylates to -Boc-benzaldimines generated in situ from α-amidosulfones, which proceeds under mild conditions.
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| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6648529 | PMC |
| http://dx.doi.org/10.1021/acsomega.8b02132 | DOI Listing |
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