水素結合の多孔な協調ポリマー: 構造的変容,吸収特性,動的研究から得られる粒子の大きさ
Kazuhiro Uemura1, Kazuya Saito, Susumu Kitagawa
1Environmental Science and Engineering, Graduate School of Science and Engineering, Yamaguchi University, Tokiwadai 2-16-1, Ube-shi, Yamaguchi 755-8611, Japan. kazu-u@yamaguchi-u.ac.jp
Journal of the American Chemical Society
|December 15, 2006
まとめ
3つの新しいコバルト ((II) コーディネーションポリマーが合成されました. 化合物3は,反転可能なゲスト分子の吸附と脱吸収を示し,脱吸収のためのゼロ順位の反応機構を有する.
科学分野:
- 協調化化学について
- マテリアルサイエンス 材料科学
- クリスタルグラフィーです.
背景:
- コーディネーションポリマー (CP) は,様々な用途を持つ結晶性材料です.
- 特定の多孔構造を持つCPの設計は,宿主-ゲストの化学反応にとって極めて重要です.
- コバルト ((II) 基のCPは,興味深い磁気および触媒特性を提供しています.
研究 の 目的:
- 新しいコバルト ((II) コーディネーションポリマーを合成し,特徴づけること.
- これらのCPの構造的特徴とゲストの組み込み能力を調査する.
- ゲストで満たされたCPの吸附-消吸収行動と反応動態を研究する.
主な方法:
- 構造的決定のための単結晶X線 difraktion.
- 特徴付けのための赤外線スペクトロスコピー.
- 熱力学分析のための微分スキャニング熱計 (DSC).
- 運動研究のための同熱吸附/脱吸収実験.
主要な成果:
- 3つの新しいコバルト (((II) コーディネーションポリマー, [CoCl2 ((4-pmna) 2) n, {[Co (((NCS) 2 ((4-pmna) 2) 2Me2CO} n, {[Co ((4-pmna) 2 (((H2O) 2) ((NO3) 2.2CH3OH} nが合成されました.
- すべてのコンパウンは,長方形の空洞を持つ二重鎖の1D"繰り返しロンボイド型"チェーンを特徴としています.
- 化合物3は,水素結合による可逆のゲスト分子 (水とメタノール) の捕獲を実証し,ゼロ級消吸収機構と100kJ/molの活性化エネルギーを示した.
結論:
- N-pyridin-4-ylmethyl) ニコチナミド (4-pmna) リガンドは,コバルトと1D協調ポリマー鎖を効果的に形成しています.
- 構造的な配置はゲストの組み込みを要求しており,コンパウンド3はホスト-ゲストの特性を有しています.
- 化合物3は,分子分離またはセンシングアプリケーションの可能性を提示する,可逆的なゲストアドソルプション/デソルプションを展示しています.
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