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Carboxylate-Catalyzed C-Silylation of Terminal Alkynes.

ABSTRACT: A carboxylate-catalyzed, metal-free C-silylation protocol for terminal alkynes is reported using a quaternary ammonium pivalate as the catalyst and commercially available N,O-bis(silyl)acetamides as silylating agents. The reaction proceeds under mild conditions, tolerates a range of functionalities, and enables concomitant O- or N-silylation of acidic OH or NH groups. A Hammett ρ value of +1.4 ± 0.1 obtained for para-substituted 2-arylalkynes is consistent with the proposed catalytic cycle involving a turnover-determining deprotonation step.

SUBMITTER: Bannykh A

PROVIDER: S-EPMC10949233 | biostudies-literature | 2024 Mar

REPOSITORIES: biostudies-literature

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Carboxylate-Catalyzed C-Silylation of Terminal Alkynes.

Bannykh Anton A Pihko Petri M PM

Organic letters 20240301 10

A carboxylate-catalyzed, metal-free C-silylation protocol for terminal alkynes is reported using a quaternary ammonium pivalate as the catalyst and commercially available N,O-bis(silyl)acetamides as silylating agents. The reaction proceeds under mild conditions, tolerates a range of functionalities, and enables concomitant O- or N-silylation of acidic OH or NH groups. A Hammett ρ value of +1.4 ± 0.1 obtained for para-substituted 2-arylalkynes is consiste ...[more]

PMID: 38428925

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