Details

Autor(en) / Beteiligte

• Ueyama, Norikazu
• Takeda, Jiro
• Yamada, Yusuke
• Onoda, Akira
• Okamura, Taka-aki
• Nakamura, Akira

Titel

Dinuclear Calcium Complexes with Intramolecularly NH···O Hydrogen-Bonded Dicarboxylate Ligands

Ist Teil von

• Inorganic chemistry, 1999-02, Vol.38 (3), p.475-478

Ort / Verlag

American Chemical Society

Erscheinungsjahr

1999

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• A novel dinuclear calcium complex, [Ca2{(2-OCO-3-CH3C6H3NHCO)2C(CH3)2}2(CH3OH)6] (1), was synthesized as a structural model of 8-coordinated Ca(II) ions in the double calcium-binding site of thermolysin. The complex has four NH···O hydrogen bonds between the amide NH and the carboxylate oxygen anion. Two types of bridging coordination of the carboxylate ligand to Ca(II) were found in 1. The amide NH forms a strong NH···O hydrogen bond with the anionic oxygen of the two carboxylate oxygens. A ligand-exchange reaction between the dinuclear calcium complex and eight equimolar amounts of 2,4,6-trimethylbenzoic acid or 2-CH3-6-t-BuCONHC6H3COOH indicates that the NH···O hydrogen bond prevents the dissociation of the Ca−O bond.