Boron
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==Boron halides== | ==Boron halides== | ||
| - | Boron trihalides exchange halogen atoms, this exchange in the 1:1 mixture of BCl<sub>3</sub>:BBr<sub>3</sub> was followed by [[EXSY]] method <cite>b11exsy</cite>. Cross peaks in the <sup>11</sup>B 2D EXSY spectrum between the signals from BCl<sub>3</sub>, BCl<sub>2</sub>Br, BClBr<sub>2</sub> and BBr<sub>3</sub> indicated exchange of single halogen atoms per molecular collision since only six cross-peaks between species different in composition by a single atom were observed. Diagonal signals were present in nearly 1:3:3:1 ratio. | + | Boron trihalides exchange halogen atoms, this exchange in the neat 1:1 mixture of BCl<sub>3</sub>:BBr<sub>3</sub> was followed by [[EXSY]] method <cite>b11exsy</cite>. Cross peaks in the <sup>11</sup>B 2D EXSY spectrum between the signals from BCl<sub>3</sub>, BCl<sub>2</sub>Br, BClBr<sub>2</sub> and BBr<sub>3</sub> indicated exchange of single halogen atoms per molecular collision since only six cross-peaks between species different in composition by a single atom were observed. Diagonal signals were present in nearly 1:3:3:1 ratio. |
==References== | ==References== | ||
Revision as of 05:08, 17 October 2008
B11 chemical shifts by Tom Cole at San Diego State University
Boron halides
Boron trihalides exchange halogen atoms, this exchange in the neat 1:1 mixture of BCl3:BBr3 was followed by EXSY method [1]. Cross peaks in the 11B 2D EXSY spectrum between the signals from BCl3, BCl2Br, BClBr2 and BBr3 indicated exchange of single halogen atoms per molecular collision since only six cross-peaks between species different in composition by a single atom were observed. Diagonal signals were present in nearly 1:3:3:1 ratio.
References
- DEROSE, EF and CASTILLO, J and SAULYS, D and MORRISON, J. A two-dimensional boron-11 NMR study of halogen scrambling in a mixture of BCl3 and BBr3. Journal of magnetic resonance 93(2):347--354, 1991. BibTeX
