コバルト触媒によるアルファオレフィンジメリゼーションにより,線形アルファオレフィン製品が得られる
Richard D Broene1, Maurice Brookhart, William M Lamanna
1Department of Chemistry, Bowdoin College, Brunswick, Maine 04011, USA. rbroene@bowdoin.edu
Journal of the American Chemical Society
|December 8, 2005
まとめ
新しいコバルト触媒は,1-ヘクセンのようなオレフィンのオリゴメリゼーションをダイマーとトリマーに容易にします. より少ない酸を使用すると,1-ブーテンから1-オクトンなどの線形アルファ-オレフィン二重体形成が促進されます.
科学分野:
- 有機金属化学 有機金属化学
- カタリシス カタリシス カタリシス
- ポリマーサイエンスの科学
背景:
- オレフィン・オリゴメリゼーションは,石油化学における重要なプロセスです.
- 選択的なオレフィン変換のための効率的な触媒の開発は極めて重要です.
- コバルト複合体は,オレフィン・オリゴメリゼーションの触媒としての可能性を秘めています.
研究 の 目的:
- オレフィンオリゴメリゼーションのための新しいコバルト複合体の触媒活性を調べる.
- 反応条件,特に酸性ステキオメトリーの影響が製品配布に及ぼす影響を調査する.
- ダイマーとトリマー形成に対する選択性を決定する.
主な方法:
- コバルト触媒 [Cp*P(OMe) 3CoCH2CH3]+[BarF]-の合成は,HBArFをCp*P(OMe) 3Co(エチネに添加することによって行われる.
- 合成した触媒を用いた1 - ヘクセンのオリゴメリゼーションは,さまざまな条件下で行われる.
- ダイマーとトリマーの識別と定量化のための反応産物の分析.
主要な成果:
- コバルト触媒は1 - ヘクセンを効果的にオリゴメライズし,ダイマーとトリマーの両方を生成します.
- 酸共触媒 (HBArF) の欠乏は,線形アルファ-オレフィン二重体形成を著しく促進する.
- 具体的な例としては,1-ブテンから1-オクテン,1-ヘクセンから1-ドデセン,1-オクテンから1-ヘクサデセンへの二酸化が含まれます.
結論:
- 研究されたコバルト複合体は,オレフィン・オリゴメリゼーションの活性触媒である.
- 酸性ステキオメトリーを制御することで,線形アルファ-オレフィンジマーを選択的に生成することができます.
- この触媒システムは,特定のオレフィンオリゴマーの標的合成の可能性を示しています.
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