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Direct ?- and ?-C(sp³ )-H Alkynylation of Free Carboxylic Acids*.

ABSTRACT: In this study we report the identification of a novel class of ligands for palladium-catalyzed C(sp³ )-H activation that enables the direct alkynylation of free carboxylic acid substrates. In contrast to previous synthetic methods, no introduction/removal of an exogenous directing group is required. A broad scope of acids including both ?-quaternary and challenging ?-non-quaternary can be used as substrates. Additionally, the alkynylation in the distal ?-position is reported. Finally, this study encompasses preliminary findings on an enantioselective variant of the title transformation as well as synthetic applications of the products obtained.

SUBMITTER: Ghiringhelli F

PROVIDER: S-EPMC7756274 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature

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Direct β- and γ-C(sp3 )-H Alkynylation of Free Carboxylic Acids*.

Ghiringhelli Francesca F Uttry Alexander A Ghosh Kiron Kumar KK van Gemmeren Manuel M

Angewandte Chemie (International ed. in English) 20201012 51

In this study we report the identification of a novel class of ligands for palladium-catalyzed C(sp3 )-H activation that enables the direct alkynylation of free carboxylic acid substrates. In contrast to previous synthetic methods, no introduction/removal of an exogenous directing group is required. A broad scope of acids including both α-quaternary and challenging α-non-quaternary can be used as substrates. Additionally, the alkynylation in the distal γ-position is reported. Finally, ...[more]

PMID: 32898310

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