Select 11B and 19F chemical shifts (in ppm) of mixtures of boranes with CsF in various solvents. Crypt = [2.2.2]-cryptand; n.r.: not resolved; n.d.: not detected.
| # | Conditions | δ 11B | δ 19F | 1 J BF/Hz |
|---|---|---|---|---|
| 1 | BEt3/CsF/CDCl3 | 11.2 | −148.3 | n.r. |
| 2 | BEt3/CsF/DCM | 9.8 | −148.3 | n.r. |
| 3 | BEt3/CsF/MeCN | 5.4 | −178.9 | 63 |
| 4 | BEt3/CsF/DCM/crypt | 5.2 | −192.0 | 89a |
| 5 | BEt3/CsF/MeCN/crypt | 4.5 | −190.2 | 88 |
| 6 | 5/CsF/MeCN | 4.1 | −153.6 | 80 |
| 7 | 1/CsF/CDCl3 | n.d. | n.d. | n.d. |
| 8 | 1/CsF/MeCN | 7.4 | −130.2 | 72 |
| 9 | 1/CsF/CDCl3/crypt | 2.9 | −144.4 | n.r. |
a
No 1JBF resolved when run in CDCl3, thus data in DCM reported.