One‐ and two‐dimensional polymers from proline and calcium bromide. Issue 4 (19th March 2015)

• Record Type: Journal Article
• Authors: Lamberts, Kevin; Şerb, Mihaela‐Diana; Englert, Ulli
• Is Part Of: Acta crystallographica. Volume 71:Issue 4(2015:Apr.)
• Page Start: 311
• Page End: 317
• Publication Date: 2015-03-19
• Subjects: Crystallography -- Periodicals; Crystals -- Periodicals; 548.3
• DOI: 10.1107/S2053229615005008
• Languages: English
• ISSNs: 2053-2296

Abstract

<abstract abstract-type="main" xml:lang="en"> <title> <x xml:space="preserve">Abstract</x> </title> <p>Reactions of calcium bromide with enantiopure and racemic proline in aqueous solution lead to two solids in which the zwitterionic amino acid acts as a bridging ligand between neighbouring cations. Depending on the chirality of the amino acid, topologically very different products are obtained. With racemic proline, bromide acts as a simple uncoordinated counter‐anion for the cationic heterochiral chains in <italic>catena</italic>‐poly[[aquacalcium(II)]‐μ‐aqua‐μ₃‐DL‐proline‐μ₂‐DL‐proline], {[Ca(C₅H₉NO₂)₂(H₂O)₂]Br₂}_{<italic>n</italic>}. In agreement with chemical intuition, only carboxylate and aqua O atoms coordinate the alkaline earth cation in a low‐symmetry arrangement. In contrast, L‐proline affords the two‐dimensional network poly[dibromidobis(μ₂‐L‐proline)calcium(II)], [CaBr₂(C₅H₉NO₂)₂]_{<italic>n</italic>}, with an unexpected CaBr₂ unit in a more regular coordination sphere.</p> </abstract>