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Organocatalytic Enantioselective Mannich Reaction: Direct Access to Chiral ?-Amino Esters.

ABSTRACT: An asymmetric Mannich reaction has been developed to generate chiral ?-amino esters in good yields with excellent enantiomeric excesses (ee, up to 99%) using a chiral bifunctional thiourea catalyst derived from (R,R)-cyclohexyldiamine. This is the first report on the addition of 3-indolinone-2-carboxylates to N-Boc-benzaldimines generated in situ from ?-amidosulfones, which proceeds under mild conditions.

SUBMITTER: Ravi Kumar G

PROVIDER: S-EPMC6648529 | biostudies-literature | 2019 Jan

REPOSITORIES: biostudies-literature

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Organocatalytic Enantioselective Mannich Reaction: Direct Access to Chiral β-Amino Esters.

Ravi Kumar G G Ramesh Boora B Yarlagadda Suresh S Sridhar Balasubramanian B Reddy B V Subba BVS

ACS omega 20190129 1

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 (R,R)-cyclohexyldiamine. This is the first report on the addition of 3-indolinone-2-carboxylates to N-Boc-benzaldimines generated in situ from α-amidosulfones, which proceeds under mild conditions. ...[more]

PMID: 31459463

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