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A Redox Auxiliary Strategy for Pyrrolidine Synthesis via Photocatalytic [3+2] Cycloaddition.

ABSTRACT: Cycloaddition reactions can be used to efficiently assemble pyrrolidine rings that are significant in a variety of chemical and biological applications. We have developed a method for the formal cycloaddition of cyclopropyl ketones with hydrazones that utlizes photoredox catalysis to enable the synthesis of a range of structurally diverse pyrrolidine rings. The key insight enabling the scope of photoredox [3+2] cycloadditions to be expanded to C=N electrophiles was the use of a redox auxiliary strategy that allowed for photoreductive activation of the cyclopropyl ketone without the need for an exogenous tertiary amine co-reductant. These conditions prevent the deleterious reductive ring-opening of the cyclopropyl substrates, enabling a range of less-reactive coupling partners to participate in this cycloaddition.

SUBMITTER: Amador AG

PROVIDER: S-EPMC6934258 | biostudies-literature | 2019 Jul

REPOSITORIES: biostudies-literature

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A Redox Auxiliary Strategy for Pyrrolidine Synthesis via Photocatalytic [3+2] Cycloaddition.

Amador Adrian G AG Sherbrook Evan M EM Yoon Tehshik P TP

Asian journal of organic chemistry 20190321 7

Cycloaddition reactions can be used to efficiently assemble pyrrolidine rings that are significant in a variety of chemical and biological applications. We have developed a method for the formal cycloaddition of cyclopropyl ketones with hydrazones that utlizes photoredox catalysis to enable the synthesis of a range of structurally diverse pyrrolidine rings. The key insight enabling the scope of photoredox [3+2] cycloadditions to be expanded to C=N electrophiles was the use of a redox auxiliary s ...[more]

PMID: 31886117

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