Table 1.
| ||||
---|---|---|---|---|
entry | cat., mol % | solvent | time/temp | yield (%)b |
1 | DEU, 20 | DMSO | 2 h/rt | 86 |
2 | DEU, 20 | DMSO | 4 h/rt | >99 (91c) |
3 | DEU, 20 | DMF | 2 h/rt | 63 |
4 | DEU, 20 | DMPU | 2 h/rt | 49 |
5 | DEU, 30 | otherd | 16 h/60 °C | 0 |
6 | DEU, 10 | DMSO | 2 h/rt | 75 |
7 | DEU, 10 | DMSO | 24 h/rt | >99 |
8 | DMPU, 130 | DMSO | 16 h/rt | 73 |
9 | – | DMSO | 64 h/rt | 7 |
Conditions: 1a (0.5 M, 1 equiv), 2a (0.63 M). rt (≈22 °C).
Determined by 19F NMR.
Isolated yield.
THF, MeOH, acetone.