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From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
Published on: March 24, 2018
Exploring the solid state and solution structural chemistry of the utility amide potassium hexamethyldisilazide
Ana I Ojeda-Amador1, Antonio J Martínez-Martínez1, Gemma M Robertson1
1WestCHEM, Department of Pure and Applied Chemistry, University of Strathclyde, 295 Cathedral Street, Glasgow, G1 1XL, UK. a.j.martinez@strath.ac.uk charlie.ohara@strath.ac.uk.
Abstract:
The structural chemistry of eleven donor complexes of the important Brønsted base potassium 1,1,1,3,3,3-hexamethyldisilazide (KHMDS) has been studied. Depending on the donor, each complex adopted one of five general structural motifs. Specifically, in this study the donors employed were toluene (to give polymeric 1 and dimeric 2), THF (polymeric 3), N,N,N',N'-tetramethylethylenediamine (TMEDA) (dimeric 4), (R,R)-N,N,N',N'-tetramethyl-1,2-diaminocyclohexane [(R,R)-TMCDA] (dimeric 5), 12-crown-4 (dimeric 6), N,N,N',N'-tetramethyldiaminoethyl ether (TMDAE) (tetranuclear dimeric 8 and monomeric 10), N,N,N',N'',N''-pentamethyldiethylenetriamine (PMDETA) (tetranuclear dimeric 7), tris[2-dimethyl(amino)ethyl]amine (Me6TREN) (tetranuclear dimeric 9) and tris{2-(2-methoxyethoxy)ethyl}amine (TMEEA) (monomeric 11). The complexes were also studied in solution by 1H and 13C NMR spectroscopy as well as DOSY NMR spectroscopy.
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