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Updated: Jul 20, 2026

Synthesis of Hypervalent Iodonium Alkynyl Triflates for the Application of Generating Cyanocarbenes
12:27

Synthesis of Hypervalent Iodonium Alkynyl Triflates for the Application of Generating Cyanocarbenes

Published on: September 8, 2013

1アルキンがアルファ,β-エノンを形成する,Rh(I) 触媒によるケレーション補助による水分性二極化

Young Jun Park1, Bong-Il Kwon, Jeong-Ae Ahn

  • 1Department of Chemistry and Center for Bioactive Molecular Hybrid (CBMH), Yonsei University, Seoul 120-749, Korea.

Journal of the American Chemical Society
|October 28, 2004
PubMed
まとめ

研究者は,アルキンと水から直接アルファ,ベータ-エノンを生産する,1-アルキンの水分性二分化のための新しい触媒システムを開発しました. アルキル置換剤は,枝分かれと線形産物の比率を制御する.

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Reduction of Alkynes to cis-Alkenes: Catalytic Hydrogenation

Introduction
Like alkenes, alkynes can be reduced to alkanes in the presence of transition metal catalysts such as Pt, Pd, or Ni. The reaction involves two sequential syn additions of hydrogen via a cis-alkene intermediate.
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Acid-Catalyzed α-Halogenation of Aldehydes and Ketones

By replacing an α-hydrogen with a halogen, acid-catalyzed α-halogenation of aldehydes or ketones yields a monohalogenated product
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Base-Promoted α-Halogenation of Aldehydes and Ketones

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α-Alkylation of Ketones via Enolate Ions

Ketones with α protons are deprotonated by strong bases like lithium diisopropylamide (LDA) to form enolate ions. The anion is stabilized by resonance, and its hybrid structure exhibits negative charges on the carbonyl oxygen and the α carbon. This ambident nucleophile can attack an electrophile via two possible sites: the carbonyl oxygen, known as O-attack, or the α carbon, known as C-attack. The nucleophilic attack via the carbanionic site is preferred. This is due to the strong interaction...
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