Cyclodextrin-Driven Formation of Double Six-Ring (D6R) Silicate Cage: NMR Spectroscopic Characterization from Solution to Crystals
Identification and isolation of secondary building units (SBUs) from synthesis media of zeolites still represent a challenging task for chemists. The cage structure anion Si<sub>12</sub>O<sub>30</sub><sup>12−</sup> known as the double six-ring (D6R) was...
| Main Authors: | , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2018-12-01
|
| Series: | Crystals |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2073-4352/8/12/457 |
| _version_ | 1798006483574587392 |
|---|---|
| author | Mohamed Haouas Clément Falaise Charlotte Martineau-Corcos Emmanuel Cadot |
| author_facet | Mohamed Haouas Clément Falaise Charlotte Martineau-Corcos Emmanuel Cadot |
| author_sort | Mohamed Haouas |
| collection | DOAJ |
| description | Identification and isolation of secondary building units (SBUs) from synthesis media of zeolites still represent a challenging task for chemists. The cage structure anion Si<sub>12</sub>O<sub>30</sub><sup>12−</sup> known as the double six-ring (D6R) was synthesized from α-cyclodextrin (α-CD) mediated alkaline silicate solutions and conditions of its stability and reactivity in aqueous solution were studied by using nuclear magnetic resonance (NMR) spectroscopy. A single crystal X-ray diffraction (XRD) analysis revealed a novel polymorph of the hybrid complex K<sub>12</sub>Si<sub>12</sub>O<sub>30</sub>·2α-CD·<i>n</i>D<sub>2</sub>O (<i>n</i> ≈ 30⁻40), which crystallizes in the orthorhombic C222<sub>1</sub> space group symmetry with a = 14.841(4) Å, b = 25.855(6) Å, and c = 41.91(1) Å. The supramolecular adduct of the silicate anion sandwiched by two α-CDs forms a perfect symmetry matching the H-bonding donor-acceptor system between the organic macrocycle and the D6R unit. The driving force of such a hybrid assembly has found to be strongly dependent on the nature of the cation present as large alkali counter ions (K<sup>+</sup>, Rb<sup>+</sup> and Cs<sup>+</sup>), which stabilize the D6R structure acting as templates. Lastly, we provided the first <sup>29</sup>Si MAS NMR measurement of <sup>3</sup>Q Si in an isolated D6R unit that allows the verification of the linear correlation between the chemical shift and <SiOSi> bond angle for <sup>3</sup>Q Si species in D<i>n</i>R cages (<i>n</i> = 3, 4, 6). |
| first_indexed | 2024-04-11T12:55:36Z |
| format | Article |
| id | doaj.art-e2accb84139e4c0889cf4fc38308d0d6 |
| institution | Directory Open Access Journal |
| issn | 2073-4352 |
| language | English |
| last_indexed | 2024-04-11T12:55:36Z |
| publishDate | 2018-12-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Crystals |
| spelling | doaj.art-e2accb84139e4c0889cf4fc38308d0d62022-12-22T04:23:05ZengMDPI AGCrystals2073-43522018-12-0181245710.3390/cryst8120457cryst8120457Cyclodextrin-Driven Formation of Double Six-Ring (D6R) Silicate Cage: NMR Spectroscopic Characterization from Solution to CrystalsMohamed Haouas0Clément Falaise1Charlotte Martineau-Corcos2Emmanuel Cadot3Institut Lavoisier de Versailles, Centre National de la Recherche Scientifique, Université de Versailles St-Quentin, Université Paris-Saclay, 45 av. des Etats-Unis, 78035 Versailles CEDEX, FranceInstitut Lavoisier de Versailles, Centre National de la Recherche Scientifique, Université de Versailles St-Quentin, Université Paris-Saclay, 45 av. des Etats-Unis, 78035 Versailles CEDEX, FranceInstitut Lavoisier de Versailles, Centre National de la Recherche Scientifique, Université de Versailles St-Quentin, Université Paris-Saclay, 45 av. des Etats-Unis, 78035 Versailles CEDEX, FranceInstitut Lavoisier de Versailles, Centre National de la Recherche Scientifique, Université de Versailles St-Quentin, Université Paris-Saclay, 45 av. des Etats-Unis, 78035 Versailles CEDEX, FranceIdentification and isolation of secondary building units (SBUs) from synthesis media of zeolites still represent a challenging task for chemists. The cage structure anion Si<sub>12</sub>O<sub>30</sub><sup>12−</sup> known as the double six-ring (D6R) was synthesized from α-cyclodextrin (α-CD) mediated alkaline silicate solutions and conditions of its stability and reactivity in aqueous solution were studied by using nuclear magnetic resonance (NMR) spectroscopy. A single crystal X-ray diffraction (XRD) analysis revealed a novel polymorph of the hybrid complex K<sub>12</sub>Si<sub>12</sub>O<sub>30</sub>·2α-CD·<i>n</i>D<sub>2</sub>O (<i>n</i> ≈ 30⁻40), which crystallizes in the orthorhombic C222<sub>1</sub> space group symmetry with a = 14.841(4) Å, b = 25.855(6) Å, and c = 41.91(1) Å. The supramolecular adduct of the silicate anion sandwiched by two α-CDs forms a perfect symmetry matching the H-bonding donor-acceptor system between the organic macrocycle and the D6R unit. The driving force of such a hybrid assembly has found to be strongly dependent on the nature of the cation present as large alkali counter ions (K<sup>+</sup>, Rb<sup>+</sup> and Cs<sup>+</sup>), which stabilize the D6R structure acting as templates. Lastly, we provided the first <sup>29</sup>Si MAS NMR measurement of <sup>3</sup>Q Si in an isolated D6R unit that allows the verification of the linear correlation between the chemical shift and <SiOSi> bond angle for <sup>3</sup>Q Si species in D<i>n</i>R cages (<i>n</i> = 3, 4, 6).https://www.mdpi.com/2073-4352/8/12/457crystallizationnuclear magnetic resonance spectroscopyhydrogen-bondingsilicate oligomersself-assemblymolecular recognitiontemplate effect |
| spellingShingle | Mohamed Haouas Clément Falaise Charlotte Martineau-Corcos Emmanuel Cadot Cyclodextrin-Driven Formation of Double Six-Ring (D6R) Silicate Cage: NMR Spectroscopic Characterization from Solution to Crystals Crystals crystallization nuclear magnetic resonance spectroscopy hydrogen-bonding silicate oligomers self-assembly molecular recognition template effect |
| title | Cyclodextrin-Driven Formation of Double Six-Ring (D6R) Silicate Cage: NMR Spectroscopic Characterization from Solution to Crystals |
| title_full | Cyclodextrin-Driven Formation of Double Six-Ring (D6R) Silicate Cage: NMR Spectroscopic Characterization from Solution to Crystals |
| title_fullStr | Cyclodextrin-Driven Formation of Double Six-Ring (D6R) Silicate Cage: NMR Spectroscopic Characterization from Solution to Crystals |
| title_full_unstemmed | Cyclodextrin-Driven Formation of Double Six-Ring (D6R) Silicate Cage: NMR Spectroscopic Characterization from Solution to Crystals |
| title_short | Cyclodextrin-Driven Formation of Double Six-Ring (D6R) Silicate Cage: NMR Spectroscopic Characterization from Solution to Crystals |
| title_sort | cyclodextrin driven formation of double six ring d6r silicate cage nmr spectroscopic characterization from solution to crystals |
| topic | crystallization nuclear magnetic resonance spectroscopy hydrogen-bonding silicate oligomers self-assembly molecular recognition template effect |
| url | https://www.mdpi.com/2073-4352/8/12/457 |
| work_keys_str_mv | AT mohamedhaouas cyclodextrindrivenformationofdoublesixringd6rsilicatecagenmrspectroscopiccharacterizationfromsolutiontocrystals AT clementfalaise cyclodextrindrivenformationofdoublesixringd6rsilicatecagenmrspectroscopiccharacterizationfromsolutiontocrystals AT charlottemartineaucorcos cyclodextrindrivenformationofdoublesixringd6rsilicatecagenmrspectroscopiccharacterizationfromsolutiontocrystals AT emmanuelcadot cyclodextrindrivenformationofdoublesixringd6rsilicatecagenmrspectroscopiccharacterizationfromsolutiontocrystals |