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Iridium-catalyzed enantioselective direct vinylogous allylic alkylation of coumarins.

ABSTRACT: The first iridium-catalyzed enantioselective vinylogous allylic alkylation of coumarins is presented. Using easily accessible linear allylic carbonates as the allylic electrophile, this reaction installs unfunctionalized allyl groups at the ?-position of 4-methylcoumarins in an exclusively branched-selective manner generally in high yields with an excellent level of enantioselectivity (up to 99?:?1 er).

SUBMITTER: Sarkar R

PROVIDER: S-EPMC6050583 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature

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Iridium-catalyzed enantioselective direct vinylogous allylic alkylation of coumarins.

Sarkar Rahul R Mitra Sankash S Mukherjee Santanu S

Chemical science 20180604 26

The first iridium-catalyzed enantioselective vinylogous allylic alkylation of coumarins is presented. Using easily accessible linear allylic carbonates as the allylic electrophile, this reaction installs unfunctionalized allyl groups at the γ-position of 4-methylcoumarins in an exclusively branched-selective manner generally in high yields with an excellent level of enantioselectivity (up to 99 : 1 er). ...[more]

PMID: 30079186

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