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Exo-selective reductive macrocyclization of ynals.

ABSTRACT: A general protocol for the highly exo-selective macrocyclization of ynals using a nickel/N-heterocyclic carbene catalyst system has been developed. A series of 10- to 21-membered macrocycles bearing an exomethylene substituent was synthesized in good yields with excellent regioselectivity (exo/endo >95:5). Very high levels of long-range diastereocontrol can also be achieved for some classes of macrocycles. Complementary to previously reported endo-selective macrocyclizations, this method provides accesses to exoalkylidene macrocycles from simple ynals in high selectivity.

SUBMITTER: Wang H

PROVIDER: S-EPMC4381747 | biostudies-literature | 2015 Mar

REPOSITORIES: biostudies-literature

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Exo-selective reductive macrocyclization of ynals.

Wang Hengbin H Negretti Solymar S Knauff Allison R AR Montgomery John J

Organic letters 20150306 6

A general protocol for the highly exo-selective macrocyclization of ynals using a nickel/N-heterocyclic carbene catalyst system has been developed. A series of 10- to 21-membered macrocycles bearing an exomethylene substituent was synthesized in good yields with excellent regioselectivity (exo/endo >95:5). Very high levels of long-range diastereocontrol can also be achieved for some classes of macrocycles. Complementary to previously reported endo-selective macrocyclizations, this method provide ...[more]

PMID: 25746060

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