Jove
Visualize
お問い合わせ
JoVE
x logofacebook logolinkedin logoyoutube logo
JoVEについて
概要リーダーシップブログJoVEヘルプセンター
著者向け
出版プロセス編集委員会範囲と方針査読よくある質問投稿
図書館員向け
推薦の声購読アクセスリソース図書館諮問委員会よくある質問
研究
JoVE JournalMethods CollectionsJoVE Encyclopedia of Experimentsアーカイブ
教育
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab Manual教員リソースセンター教員サイト
利用規約
プライバシーポリシー
ポリシー

関連する概念動画

Reduction of Alkenes: Asymmetric Catalytic Hydrogenation02:17

Reduction of Alkenes: Asymmetric Catalytic Hydrogenation

3.8K
Catalytic hydrogenation of alkenes is a transition-metal catalyzed reduction of the double bond using molecular hydrogen to give alkanes. The mode of hydrogen addition follows syn stereochemistry.
The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...
3.8K
Reduction of Alkynes to cis-Alkenes: Catalytic Hydrogenation02:24

Reduction of Alkynes to cis-Alkenes: Catalytic Hydrogenation

8.9K
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.
8.9K
Reduction of Alkenes: Catalytic Hydrogenation02:13

Reduction of Alkenes: Catalytic Hydrogenation

13.8K
Alkenes undergo reduction by the addition of molecular hydrogen to give alkanes. Because the process generally occurs in the presence of a transition-metal catalyst, the reaction is called catalytic hydrogenation.
Metals like palladium, platinum, and nickel are commonly used in their solid forms — fine powder on an inert surface. As these catalysts remain insoluble in the reaction mixture, they are referred to as heterogeneous catalysts.
The hydrogenation process takes place on the...
13.8K
Alkynes to Aldehydes and Ketones: Hydroboration-Oxidation02:47

Alkynes to Aldehydes and Ketones: Hydroboration-Oxidation

20.5K
Introduction
One of the convenient methods for the preparation of aldehydes and ketones is via hydration of alkynes. Hydroboration-oxidation of alkynes is an indirect hydration reaction in which an alkyne is treated with borane followed by oxidation with alkaline peroxide to form an enol that rapidly converts into an aldehyde or a ketone. Terminal alkynes form aldehydes, whereas internal alkynes give ketones as the final product.
20.5K
Reduction of Benzene to Cyclohexane: Catalytic Hydrogenation01:28

Reduction of Benzene to Cyclohexane: Catalytic Hydrogenation

5.6K
Unlike the easy catalytic hydrogenation of an alkene double bond, hydrogenation of a benzene double bond under similar reaction conditions does not take place easily. For example, in the reduction of stilbene, the benzene ring remains unaffected while the alkene bond gets reduced. Hydrogenation of an alkene double bond is exothermic and a favorable process. In contrast, to hydrogenate the first unsaturated bond of benzene, an energy input is needed; that is, the process is endothermic. This is...
5.6K
Regioselectivity and Stereochemistry of Hydroboration02:36

Regioselectivity and Stereochemistry of Hydroboration

9.3K
A significant aspect of hydroboration–oxidation is the regio- and stereochemical outcome of the reaction.
Hydroboration proceeds in a concerted fashion with the attack of borane on the π bond, giving a cyclic four-centered transition state. The –BH2 group is bonded to the less substituted carbon and –H to the more substituted carbon. The concerted nature requires the simultaneous addition of –H and –BH2 across the same face of the alkene giving syn stereochemistry.
9.3K

こちらも読む

関連記事

共著者、ジャーナル、引用グラフによってこの研究に関連する記事。

並び替え
Same author

Cryo-EM structures of photosystem I with alternative quinones reveals new insight into cofactor selectivity.

bioRxiv : the preprint server for biology·2026
Same author

Cryo-EM structure of a photosystem I variant containing an unusual plastoquinone derivative in its electron transfer chain.

Science advances·2024
Same author

Structure of methylaluminoxane (MAO): Extractable [Al(CH<sub>3</sub>)<sub>2</sub>]<sup>+</sup> for precatalyst activation.

Science (New York, N.Y.)·2024
Same author

Cationic Cobalt(II) Bisphosphine Hydroformylation Catalysis: In Situ Spectroscopic and Reaction Studies.

Journal of the American Chemical Society·2023
Same author

A low-cost and realistic noisy light system for studying photosynthesis.

Photosynthesis research·2023
Same author

Chloride facilitates Mn(III) formation during photoassembly of the Photosystem II oxygen-evolving complex.

Photosynthesis research·2021

関連する実験動画

Updated: Dec 29, 2025

Synthesis of Metal Nanoparticles Supported on Carbon Nanotube with Doped Co and N Atoms and its Catalytic Applications in Hydrogen Production
08:40

Synthesis of Metal Nanoparticles Supported on Carbon Nanotube with Doped Co and N Atoms and its Catalytic Applications in Hydrogen Production

Published on: December 6, 2021

4.1K

高活性カチオンコバルト (II) 水酸化触媒

Drew M Hood1, Ryan A Johnson1, Alex E Carpenter2

  • 1Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA.

Science (New York, N.Y.)
|February 1, 2020
PubMed
まとめ

新しいカチオンのコバルト触媒は,アルケンの水酸化に高い活性と選択性を提供し,ロジウムの性能に接近します. これらの触媒は,特に内部アルケンの場合,長寿命と安定性を示しています.

さらに関連する動画

A Simple, Low-cost, and Robust System to Measure the Volume of Hydrogen Evolved by Chemical Reactions with Aqueous Solutions
06:32

A Simple, Low-cost, and Robust System to Measure the Volume of Hydrogen Evolved by Chemical Reactions with Aqueous Solutions

Published on: August 17, 2016

20.2K
Developing Photosensitizer-Cobaloxime Hybrids for Solar-Driven H2 Production in Aqueous Aerobic Conditions
10:21

Developing Photosensitizer-Cobaloxime Hybrids for Solar-Driven H2 Production in Aqueous Aerobic Conditions

Published on: October 5, 2019

8.8K

関連する実験動画

Last Updated: Dec 29, 2025

Synthesis of Metal Nanoparticles Supported on Carbon Nanotube with Doped Co and N Atoms and its Catalytic Applications in Hydrogen Production
08:40

Synthesis of Metal Nanoparticles Supported on Carbon Nanotube with Doped Co and N Atoms and its Catalytic Applications in Hydrogen Production

Published on: December 6, 2021

4.1K
A Simple, Low-cost, and Robust System to Measure the Volume of Hydrogen Evolved by Chemical Reactions with Aqueous Solutions
06:32

A Simple, Low-cost, and Robust System to Measure the Volume of Hydrogen Evolved by Chemical Reactions with Aqueous Solutions

Published on: August 17, 2016

20.2K
Developing Photosensitizer-Cobaloxime Hybrids for Solar-Driven H2 Production in Aqueous Aerobic Conditions
10:21

Developing Photosensitizer-Cobaloxime Hybrids for Solar-Driven H2 Production in Aqueous Aerobic Conditions

Published on: October 5, 2019

8.8K

科学分野:

  • 有機金属化学
  • カタリシス
  • 有機合成

背景:

  • 水酸化は伝統的にコバルトやロジウム触媒を用いる.
  • ロジウム触媒は活性度が高いが,高価である.
  • 現存するコバルト触媒は活性と選択性において制限があります.

研究 の 目的:

  • 活性と選択性を高める新しいコバルト触媒の開発
  • 新しいコバルト触媒の性能を既存の産業標準と比較する.
  • 異なるアルケンのタイプに対するこれらの触媒の地域選択性を調査する.

主な方法:

  • カチオンコバルトの合成 (II) ビスフォスフィンの水素カルボニル複合体
  • アルケンの水酸化における触媒作用の評価
  • 各種のアルケンの線形から枝分かれ (L:B) 領域選択性の分析.
  • 触媒の安定性と寿命の評価

主要な成果:

  • 新しいカチオンのコバルト触媒は,従来のコバルト (I) 触媒よりも著しく高い活性を示します.
  • 触媒の活性度は高価なロジウム・フォスフィンの触媒に近い.
  • 単純な線形アルケンの低L:B地域選択性が見られた.
  • イソメリゼーションとステリック効果により,アルキル分岐を持つ内部アルケンの高いL:B地域選択性が達成される.
  • 触媒は長い寿命と分解への耐性を示しています.

結論:

  • カチオンコバルトビスホスフィンの触媒は,水酸化過程の有望な進歩を表しています.
  • これらの触媒はロジウム触媒の費用対効果の高い代替品です.
  • 内部アルケンの選択性は,これらの新しいシステムで達成可能である.