Preparation and NMR characterization of carbenium ions on metal halide powders
- Texas A & M Univ., College Station, TX (United States)
We report that a wide variety of carbenium ions and related electrophilic species can be prepared by the direct contact of suitable precursors with metal halide powders at reasonable temperatures and in the absence of solvent, permitting direct measurement of the principal components of the {sup 13}C chemical shift tensors. {sup 1}H MAS experiments showed that the proton content of our AlCl{sub 3} powder was low and could be further reduced by extended evacuation. By measuring the {sup 31}P spectrum of adsorbed P(CH{sub 3}){sub 3}, following the work of Lunsford and co-workers, we established that Lewis sites greatly exceeded Bronsted sites on our AlCl{sub 3} powder. We believe that significant progress in solid superacid chemistry awaits the application of NMR to adsorbates on a variety of metal halides, mixed salts, and salts treated with hydrogen halides. 22 refs., 3 figs., 1 tab.
- Sponsoring Organization:
- USDOE
- DOE Contract Number:
- FG03-93ER14354
- OSTI ID:
- 111189
- Journal Information:
- Journal of the American Chemical Society, Journal Name: Journal of the American Chemical Society Journal Issue: 30 Vol. 117; ISSN JACSAT; ISSN 0002-7863
- Country of Publication:
- United States
- Language:
- English
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