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Structural Elucidation of the Mechanism of Molecular Recognition in Chiral Crystalline Sponges.

ABSTRACT: To gain insight into chiral recognition in porous materials we have prepared a family of fourth generation chiral metal-organic frameworks (MOFs) that have rigid frameworks and adaptable (flexible) pores. The previously reported parent material, [Co2 (S-mandelate)2 (4,4'-bipyridine)3 ](NO3 )2 , CMOM-1S, is a modular MOF; five new variants in which counterions (BF4 - , CMOM-2S) or mandelate ligands are substituted (2-Cl, CMOM-11R; 3-Cl, CMOM-21R; 4-Cl, CMOM-31R; 4-CH3 , CMOM-41R) and the existing CF3 SO3 - variant CMOM-3S are studied herein. Fine-tuning of pore size, shape, and chemistry afforded a series of distinct host-guest binding sites with variable chiral separation properties with respect to three structural isomers of phenylpropanol. Structural analysis of the resulting crystalline sponge phases revealed that host-guest interactions, guest-guest interactions, and pore adaptability collectively determine chiral discrimination.

SUBMITTER: Zhang SY

PROVIDER: S-EPMC7540565 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature

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Structural Elucidation of the Mechanism of Molecular Recognition in Chiral Crystalline Sponges.

Zhang Shi-Yuan SY Fairen-Jimenez David D Zaworotko Michael J MJ

Angewandte Chemie (International ed. in English) 20200811 40

To gain insight into chiral recognition in porous materials we have prepared a family of fourth generation chiral metal-organic frameworks (MOFs) that have rigid frameworks and adaptable (flexible) pores. The previously reported parent material, [Co2 (S-mandelate)2 (4,4'-bipyridine)3 ](NO3 )2 , CMOM-1S, is a modular MOF; five new variants in which counterions (BF4- , CMOM-2S) or mandelate ligands are substituted (2-Cl, ...[more]

PMID: 32589318

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