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Decarboxylative benzylations of alkynes and ketones.

ABSTRACT: Benzyl esters of propiolic and beta-keto acids undergo catalytic decarboxylative coupling when treated with appropriate palladium catalysts. Such decarboxylative couplings allow the benzylation of alkynes without the use of strong bases and/or organometallics. This allows the synthesis of sensitive benzylic alkynes that are prone to undergo isomerizations under basic conditions. Additionally, decarboxylation facilitates the site-specific benzylation of diketones and ketoesters under mild, base-free conditions. Ultimately, the methodology described expands our ability to cross-couple medicinally relevant heterocycles.

SUBMITTER: Torregrosa RR

PROVIDER: S-EPMC2923406 | biostudies-literature | 2010 Jul

REPOSITORIES: biostudies-literature

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Decarboxylative benzylations of alkynes and ketones.

Torregrosa Robert R P RR Ariyarathna Yamuna Y Chattopadhyay Kalicharan K Tunge Jon A JA

Journal of the American Chemical Society 20100701 27

Benzyl esters of propiolic and beta-keto acids undergo catalytic decarboxylative coupling when treated with appropriate palladium catalysts. Such decarboxylative couplings allow the benzylation of alkynes without the use of strong bases and/or organometallics. This allows the synthesis of sensitive benzylic alkynes that are prone to undergo isomerizations under basic conditions. Additionally, decarboxylation facilitates the site-specific benzylation of diketones and ketoesters under mild, base-f ...[more]

PMID: 20565096

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