ディフォスフィン・フォスフェニウム協調複合体は,ペンダントドナーを持つモノケーションとリガンド結合ドケーションを代表する
Neil Burford1, David E Herbert, Paul J Ragogna
1Department of Chemistry, Dalhousie University, Halifax, Nova Scotia, B3H 4J3, Canada. Neil.Burford@dal.ca
Journal of the American Chemical Society
|December 23, 2004
まとめ
研究者らは,リン基のルイス酸とリンガンドを用いて,新種のトリフォスファルモノケーションとテトラフォスファルディケーションを作り出した. これらの研究は,同原子のP-P結合と協調化学を調査し,リガンドの柔軟性およびステリック因子に基づく構造的好みを明らかにします.
科学分野:
- * 無機化学 無機化学
- * 有機金属化学について
- * リン化学 リン化学
背景:
- *ホモアトミックP-P結合は,リン化学の重要な分野である.
- * フォスフェニウムイオン (R2P+) は重要なルイス酸である.
- * ディフォスフィン・リガンドは,多用途の協調モードを提供します.
研究 の 目的:
- *新型のトライフォスファルモノケーションとテトラフォスファルディケーションを合成し,特徴づけること.
- * フォスフェニウム受容体とのディフォスフィンリガンドの調整行動を調査する.
- *これらのリン酸集群における構造的好みに影響する要因を調査する.
主な方法:
- * リン含有モノケーションとディケーションの合成.
- * 固体構造の決定のためのX線結晶学.
- *特性を定めるためのスペクトロスコピー技術 (例えば,NMR,質量スペクトロメトリー)
主要な成果:
- * トリフォスファルモノケーションとテトラフォスファルディケーションの最初の例が作成されました.
- *モノカシオンは,ディホスフィンのリガンドの1つのドナー部位のみで協調性を示し,ケレーションは観察されていません.
- * テトラフォスフォース二酸化物は,より長いディフォスフィンで形成され,2つのフォスフェニウム受容体を結合します.
- * 構造的好みは,分子内固体相互作用とリガンド結合の柔軟性に依存する.
結論:
- *ホモアトミックなP-P座標結合により,前例のない量のリンパポリケーションが形成されます.
- * リンガンドの設計とステリック要因が,協調モードと結果の構造を決定する.
- * この研究は,リン群と協調化合物の既知の化学を拡張しています.
関連する概念動画
Metal-Ligand Bonds
The hemoglobin in the blood, the chlorophyll in green plants, vitamin B-12, and the catalyst used in the manufacture of polyethylene all contain coordination compounds. Ions of the metals, especially the transition metals, are likely to form complexes.
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
Ligand Binding and Linkage
Allosteric proteins have more than one ligand binding site; the binding of a ligand to any of these sites influences the binding of ligands to the other sites. When a protein is allosteric, its binding sites are called coupled or linked. In the case of enzymes, the site that binds to the substrate is known as the active site and the other site is known as the regulatory site. When a ligand binds to the regulatory site, this leads to conformational changes in the protein that can influence the...
Protein Complexes with Interchangeable Parts
Groups of proteins may form a complex where each protein in this complex has a different role in the overall execution of the complex’s function. Often some of the proteins in the complex can be replaced by a closely related variant to give a complex that contains many of the same components yet is functionally distinct.
The SCF ubiquitin ligase is a protein complex of five individual proteins. This complex attaches ubiquitin to other target proteins to mark them for degradation. In order to...
The SCF ubiquitin ligase is a protein complex of five individual proteins. This complex attaches ubiquitin to other target proteins to mark them for degradation. In order to...
Protein Complexes with Interchangeable Parts
Groups of proteins may form a complex where each protein in this complex has a different role in the overall execution of the complex’s function. Often some of the proteins in the complex can be replaced by a closely related variant to give a complex that contains many of the same components yet is functionally distinct.
The SCF ubiquitin ligase is a protein complex of five individual proteins. This complex attaches ubiquitin to other target proteins to mark them for degradation. In order to...
The SCF ubiquitin ligase is a protein complex of five individual proteins. This complex attaches ubiquitin to other target proteins to mark them for degradation. In order to...
Complexation Equilibria: The Chelate Effect
In complexation reactions, metal atoms or cations interact with ligands to form donor-acceptor adducts called metal complexes. Ligands that bind through one donor site are monodentate, ligands with two donor sites are bidentate, and those with more than two donor sites are polydentate ligands. For example, ethylene diamine is a bidentate ligand that binds through two nitrogen donor atoms, forming a five-membered ring. EDTA is a polydentate ligand that binds through four oxygen and two nitrogen...
Complexometric Titration: Ligands
Different monodentate and polydentate ligands are used as complexing agents in complexometric titration reactions. The formation of complexes by mono- and bidentate ligands involves two or more intermediate steps, limiting their use as complexing agents. In comparison, polydentate ligands can form complexes with metal ions in a single-step process, facilitating sharper end points. This means polydentate ligands, such as amino carboxylic acid derivatives, are most commonly employed in...


