Alkylation of Terminal Alkynes under Zinc Lewis Acid Catalysis and Its Mechanistic Studies

Mana Osano, Takeru Kida, Kyohei Yonekura, Teruhisa Tsutimoto

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

With a zinc Lewis acid catalyst and proton sponge in toluene, terminal alkynes were found to undergo the alkylation by alkyl triflates to provide unsymmetrical internal alkynes. This is the first example that a simple alkyl chain other than benzylic and norbornyl units can be introduced onto the alkynyl carbon atom under Lewis acid catalysis. Mechanistic studies revealed that the activation of the alkyne by the zinc Lewis acid and proton sponge is the trigger of the reaction to give a monoalkynylzinc species, which successively reacts with the alkyl triflate to afford the internal alkyne. A radical pathway is unlikely in this system. (Figure presented.).

Original languageEnglish
Pages (from-to)2825-2831
Number of pages7
JournalAdvanced Synthesis and Catalysis
Volume361
Issue number12
DOIs
Publication statusPublished - 18 Jun 2019

Fingerprint

Lewis Acids
Alkynes
Alkylation
Catalysis
Zinc
Acids
Protons
Toluene
Chemical activation
Atoms
Catalysts
Carbon

Keywords

  • Alkylation
  • Alkynes
  • Chemoselectivity
  • Lewis acids
  • Zinc

Cite this

Osano, Mana ; Kida, Takeru ; Yonekura, Kyohei ; Tsutimoto, Teruhisa. / Alkylation of Terminal Alkynes under Zinc Lewis Acid Catalysis and Its Mechanistic Studies. In: Advanced Synthesis and Catalysis. 2019 ; Vol. 361, No. 12. pp. 2825-2831.
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Alkylation of Terminal Alkynes under Zinc Lewis Acid Catalysis and Its Mechanistic Studies. / Osano, Mana; Kida, Takeru; Yonekura, Kyohei; Tsutimoto, Teruhisa.

In: Advanced Synthesis and Catalysis, Vol. 361, No. 12, 18.06.2019, p. 2825-2831.

Research output: Contribution to journalArticle

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