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A Tandem Iridium-Catalyzed "Chain-Walking"/Cope Rearrangement Sequence.

ABSTRACT: An iridium-catalyzed tandem olefin migration/Cope rearrangement of alkenyl ?-ene cyclopropanes is reported. By this means, a variety of complex annulenes are obtained as single diastereomers starting from cyclopropyl ester derived from simple 1,?-dienes and alkenyldiazo compounds. Long-range olefin migration over up to 10 positions could be realized and coupled with an efficient Cope rearrangement to yield valuable scaffolds. Various functional groups are well-tolerated, giving rise to densely functionalized products. Furthermore, the present methodology could be successfully extended to yield bicyclic cycloheptenones starting from readily available alkenyl cyclopropanols via a Kulinkovich reaction.

SUBMITTER: Sommer H

PROVIDER: S-EPMC7493306 | biostudies-literature | 2019 Mar

REPOSITORIES: biostudies-literature

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A Tandem Iridium-Catalyzed "Chain-Walking"/Cope Rearrangement Sequence.

Sommer Heiko H Weissbrod Tal T Marek Ilan I

ACS catalysis 20190205 3

An iridium-catalyzed tandem olefin migration/Cope rearrangement of alkenyl ω-ene cyclopropanes is reported. By this means, a variety of complex annulenes are obtained as single diastereomers starting from cyclopropyl ester derived from simple 1,ω-dienes and alkenyldiazo compounds. Long-range olefin migration over up to 10 positions could be realized and coupled with an efficient Cope rearrangement to yield valuable scaffolds. Various functional groups are well-tolerated, giving rise to densely f ...[more]

PMID: 32953237

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