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Formal [4 + 2] cycloaddition of imines with alkoxyisocoumarins.

ABSTRACT: A new preparation of ?-lactams is reported. In the presence of a Lewis acid promoter, alkoxyisocoumarins engage a range of N-aryl and N-alkyl imines to form ?-lactams with a pendent carboalkoxy substituent. A sulfonamide-thiourea catalyst enables the synthesis of these products in moderate to good enantioselectivities.

SUBMITTER: Jarvis CL

PROVIDER: S-EPMC6082175 | biostudies-literature | 2018 Jun

REPOSITORIES: biostudies-literature

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Formal [4 + 2] cycloaddition of imines with alkoxyisocoumarins.

Jarvis Claire L CL Jemal Neyra M NM Knapp Spencer S Seidel Daniel D

Organic & biomolecular chemistry 20180601 23

A new preparation of δ-lactams is reported. In the presence of a Lewis acid promoter, alkoxyisocoumarins engage a range of N-aryl and N-alkyl imines to form δ-lactams with a pendent carboalkoxy substituent. A sulfonamide-thiourea catalyst enables the synthesis of these products in moderate to good enantioselectivities. ...[more]

PMID: 29796555

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