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In coordination chemistry, clathrochelates are ligands that encapsulate metal ions. Chelating ligands bind to metals more strongly than related monodentate ligands, and macrocyclic ligands bind more strongly than typical chelating ligands. It follows, that bi- or polymacrocyclic ligands would bind to metals particularly strongly. Clathrochelates are usually derived from bimacrocyclic ligands.〔Yan Z. Voloshin, Nina A.a Kostromina, Roland Krämer "Clathrochelates: synthesis, structure, and properties" Elsevier, Amsterdam, 2002. ISBN 0-444-51223-3. 〕 The first examples were derived from the tris(dioximate)s of cobalt(II) and iron(II). The synthesis entails replacement of the hydrogen-bonded proton center with BF2+ or BOR2+ group: :()2− + 2 BF3 → Fe(ON=CMeCMe=NO)3(BF)2 + 2 HF2− Also well known are the clathrochelates called sepulchrates derived from tris(ethylenediamine)cobalt(III): :()3+ + 6 CH2O + 2 NH3 → 2+. In the absence of the special geometry imposed by the clathrochelate, the lifetime of Co(II)-amine complexes is typically very short. In this way, this family of complexes enables studies on self-exchange redox reactions between Co(II) and Co(III) partners that would be impossible with simpler ligand systems. ==See also== * Cryptand 抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)』 ■ウィキペディアで「Clathrochelate」の詳細全文を読む スポンサード リンク
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