カチオンのビスホスフィン一酸化物-パラジウム複合体を用いて機能的なポリオレフィン合成
1Department of Chemistry and Biotechnology, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
Journal of the American Chemical Society
|May 18, 2012
まとめ
新しいカチオンパラジウム複合体は,多様な極性モノマーとのエチレン共聚化を可能にし,ランダムな機能群を持つ線形ポリマーを生成します. これにより,機能的なポリオレフィンに対する,既存のフォスフィン-硫酸塩系を超えて,触媒的選択肢が拡大されます.
科学分野:
- ポリマー化学のポリマー化学について
- 有機金属化学 有機金属化学
- マテリアルサイエンス 材料科学
背景:
- エチレンと極性ビニル単体との共聚合は,極性機能群との触媒の不適合性のために困難です.
- ブルックハート型α-ダイミンパラジウム複合体のような既存の触媒は,工業的に重要な極性モノマーに限られた適用性を持っています.
- フォスフィン硫酸塩結合パラジウム複合体は,このような反応のための触媒の既知のクラスです.
研究 の 目的:
- ビスホスフィン一酸化物 (BPMO) によって結合されたカチオンパラジウム複合体の有効性を,様々な極性ビニル単体とのエチレン共聚化で探求する.
- 線形機能ポリオレフィンを作るための代替的触媒システムを実証する.
- 既存のシステムとBPMO結合パラジウム触媒の性能を比較する.
主な方法:
- ビスホスフィン一酸化物 (BPMO) リガンドを含むカチオンパラジウム複合体の合成と特徴付け.
- エチレンと極性ビニルモノマー (ビニルアセテート,アクリロニトリル,ビニルエーテル,アリルモノマー) の共聚合反応は,開発された触媒を用いて行われます.
- コポリマーの微細構造の分析,線形性と極性群の分布を含む.
主要な成果:
- カチオンパラジウム-BPMO複合体は,一系列の極性ビニルモノマーでエチレンの共聚合を効果的に触媒化した.
- その結果生成されたコポリマーは,高度に線形的な微細構造と,極性機能群のランダム分布を示した.
- これらの触媒は良好な活性を示し,特定のモノメア組合せの特定の確立されたシステムを上回った.
結論:
- カチオンパラジウム-BPMO複合体は,線形機能ポリオレフィン合成のための実行可能で活性な触媒システムです.
- この研究は,極性モノマーによるパラジウム触媒によるエチレン共聚合の範囲を拡大する.
- ビスホスフィン一酸化物結合パラジウム複合体は,機能的なポリオレフィンを生成するために,フォスフィン-硫酸塩系に新しい代替案を提供します.
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