Spirocyclic zwitterionic lambda5Si-silicates with two bidentate ligands derived from alpha-amino acids or alpha-hydroxycarboxylic acids: synthesis, structure, and stereodynamics.

Reinhold Tacke; Rüdiger Bertermann; Christian Burschka; Simona Dragota; Martin Penka; Ingo Richter

doi:10.1021/ja047248z

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Spirocyclic zwitterionic lambda5Si-silicates with two bidentate ligands derived from alpha-amino acids or alpha-hydroxycarboxylic acids: synthesis, structure, and stereodynamics.

Reinhold Tacke·Rüdiger Bertermann·Christian Burschka·Simona Dragota·Martin Penka·Ingo Richter

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Abstract

A series of zwitterionic lambda(5)Si-silicates with a (2,2,6,6-tetramethylpiperidinio)methyl group and two identical bidentate ligands derived from glycine, (S)-alanine, (S)-phenylalanine, glycolic acid, (S)-lactic acid, (S)-3-phenyllactic acid, or (S)-mandelic acid were synthesized and structurally characterized (solution and solid-state NMR spectroscopy; single-crystal X-ray diffraction). The chiral lambda(5)Si-silicates with ligands derived from optically active alpha-amino acids or alpha-hydroxycarboxylic acids were isolated as enantiomerically and diastereomerically pure compounds that undergo a (Lambda)/(Delta)-epimerization in solution.

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Amino Acids Carboxylic Acids Ions Kinetics Ligands Magnetic Resonance Spectroscopy Models, Molecular Molecular Structure Silicates Stereoisomerism Journal Article Research Support, Non-U.S. Gov't

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Reinhold Tacke, Rüdiger Bertermann, Christian Burschka, Simona Dragota, Martin Penka, Ingo Richter. 2004-11-10. Spirocyclic zwitterionic lambda5Si-silicates with two bidentate ligands derived from alpha-amino acids or alpha-hydroxycarboxylic acids: synthesis, structure, and stereodynamics.. https://doi.org/10.1021/ja047248z

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