Disordered sodium alkoxides from powder data: crystal structures of sodium ethoxide, propoxide, butoxide and pentoxide, and some of their solvates
- The crystal structures of sodium ethoxide (sodium ethanolate, NaOEt), sodium n-propoxide (sodium n-propanolate, NaOnPr), sodium n-butoxide (sodium n-butanolate, NaOnBu) and sodium n-pentoxide (sodium n-amylate, NaOnAm) were determined from powder X-ray diffraction data. NaOEt crystallizes in space group P421m, with Z = 2, and the other alkoxides crystallize in P4/nmm, with Z = 2. To resolve space-group ambiguities, a Bärnighausen tree was set up, and Rietveld refinements were performed with different models. In all structures, the Na and O atoms form a quadratic net, with the alkyl groups pointing outwards on both sides (anti-PbO type). The alkyl groups are disordered. The disorder becomes even more pronounced with increasing chain length. Recrystallization from the corresponding alcohols yielded four sodium alkoxide solvates: sodium ethoxide ethanol disolvate (NaOEt·2EtOH), sodium n-propoxide n-propanol disolvate (NaOnPr·2nPrOH), sodium isopropoxide isopropanol pentasolvate (NaOiPr·5iPrOH) and sodium tert-amylate tert-amyl alcohol monosolvate (NaOtAm·tAmOH, tAm = 2-methyl-2-butyl). Their crystal structures were determined by single-crystal X-ray diffraction. All these solvates form chain structures consisting of Na+, –O− and –OH groups, encased by alkyl groups. The hydrogen-bond networks diverge widely among the solvate structures. The hydrogen-bond topology of the iPrOH network in NaOiPr·5iPrOH shows branched hydrogen bonds and differs considerably from the networks in pure crystalline iPrOH.
Author: | Maurice BeskeORCiD, Stephanie CronjeORCiD, Martin U. SchmidtGND, Lukas TapmeyerORCiDGND |
---|---|
URN: | urn:nbn:de:hebis:30:3-638764 |
DOI: | https://doi.org/10.1107/S205252062001584X |
ISSN: | 2052-5206 |
Parent Title (English): | Acta crystallographica / Section B |
Publisher: | Wiley-Blackwell |
Place of publication: | Oxford [u.a.] |
Document Type: | Article |
Language: | English |
Date of Publication (online): | 2021/01/25 |
Date of first Publication: | 2021/01/25 |
Publishing Institution: | Universitätsbibliothek Johann Christian Senckenberg |
Release Date: | 2022/03/16 |
Tag: | Bärnighausen tree; PXRD; isopropanol; powder data; sodium alkoxide; solvate |
Volume: | 77 |
Issue: | 1 |
Page Number: | 15 |
First Page: | 68 |
Last Page: | 82 |
Note: | Open access funding enabled and organized by Projekt DEAL. |
HeBIS-PPN: | 492978980 |
Institutes: | Biochemie, Chemie und Pharmazie |
Dewey Decimal Classification: | 5 Naturwissenschaften und Mathematik / 53 Physik / 530 Physik |
5 Naturwissenschaften und Mathematik / 54 Chemie / 540 Chemie und zugeordnete Wissenschaften | |
Sammlungen: | Universitätspublikationen |
Licence (German): | Creative Commons - Namensnennung 4.0 |