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Cooperative Chiral Lewis Base/Palladium-Catalyzed Asymmetric Syntheses of Methylene-Containing δ-Lactams.

ABSTRACT: We herein report a two-step approach for the enantioselective synthesis of novel chiral δ-lactams. By using a cooperative chiral ITU/achiral Pd-catalyst system, this protocol proceeds via an asymmetric α-allylation of activated aryl esters first, followed by an acid-mediated lactam formation. A variety of differently substituted products could be obtained with usually high levels of enantioselectivities and in reasonable yields (16 examples, up to 98 : 2 er and 73 % yield over two steps). In addition, further utilizations of the products via transformations of the exocyclic double bond were successfully carried out as well.

SUBMITTER: Zebrowski P

PROVIDER: S-EPMC11005102 | biostudies-literature | 2023 Dec

REPOSITORIES: biostudies-literature

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Cooperative Chiral Lewis Base/Palladium-Catalyzed Asymmetric Syntheses of Methylene-Containing δ-Lactams.

Zebrowski Paul P Monkowius Uwe U Waser Mario M

European journal of organic chemistry 20231109 45

We herein report a two-step approach for the enantioselective synthesis of novel chiral δ-lactams. By using a cooperative chiral ITU/achiral Pd-catalyst system, this protocol proceeds via an asymmetric α-allylation of activated aryl esters first, followed by an acid-mediated lactam formation. A variety of differently substituted products could be obtained with usually high levels of enantioselectivities and in reasonable yields (16 examples, up to 98 : 2 er and 73 % yield over two steps). In add ...[more]

PMID: 38601429

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