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Updated: May 11, 2026

Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
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Isolating Free Carbenes, their Mixed Dimers and Organic Radicals

Published on: April 19, 2019

アルキン-カルベンの交差点における化学:メタラサイクロブテン-η3-ビニルカルベンの均衡化

Joseph M O'Connor1, Kim K Baldridge, Carmen L Vélez

  • 1Department of Chemistry, University of California, San Diego, La Jolla, California 92093, USA. jmoconnor@ucsd.edu

Journal of the American Chemical Society
|June 1, 2013
PubMed
まとめ

研究者は,ステリカルに阻害された金属サイクロブテン複合体を合成し,最初の金属サイクロブテン-η(3) -ビニルカルベンの均衡を観察しました. この発見は,有機金属化学と反応機構に関する新しい道を開く.

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Preparation of Alkynes: Alkylation Reaction

Introduction
Alkylation of terminal alkynes with primary alkyl halides in the presence of a strong base like sodium amide is one of the common methods for the synthesis of longer carbon-chain alkynes. For example, treatment of 1-propyne with sodium amide followed by reaction with ethyl bromide yields 2-pentyne.
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Electrophilic Addition to Alkynes: Halogenation

Introduction
Halogenation is another class of electrophilic addition reactions where a halogen molecule gets added across a π bond. In alkynes, the presence of two π bonds allows for the addition of two equivalents of halogens (bromine or chlorine). The addition of the first halogen molecule forms a trans-dihaloalkene as the major product and the cis isomer as the minor product. Subsequent addition of the second equivalent yields the tetrahalide.
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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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