Table 5.
Various non-oxidizing alcohols as additives.
 | |||||
|---|---|---|---|---|---|
| entry | additive | time | conversion[b] | alcohol ee[c] | s |
| 1 | none | 5.5 h | 31% | 35% | 12 |
| 2 | n-BuOH (1.0 equiv) | 5.5 h | 66% | 98% | 12 |
| 3 | n-BuOH (2.0 equiv) | 5.5 h | 67% | 95% | 10 |
| 4 | n-BuOH (8.0 equiv) | 19 h | 48% | 56% | 7 |
| 5 | CF3CH2OH (1.0 equiv) | 5.5 h | 60% | 89% | 11 |
| 6 | CF3CH2OH (2.0 equiv) | 5.5 h | 42% | 48% | 8 |
| 7 | CF3CH2OH (8.0 equiv) | 19 h | 19% | 16% | 6 |
| 8 | t-BuOH (1.0 equiv) | 22.5 h[d] | 57% | 90% | 16 |
| 9 | t-BuOH (4.0 equiv) | 11.5 h[d] | 57% | 94% | 20 |
| 10 | t-BuOH (8.0 equiv) | 19 h[e] | 57% | 90% | 16 |
[a]
10 mol% [Pd(nbd)Cl2], 10 mol% (−)-sparteine, 10 mol% Cs2CO3, 1 atm O2, 500 mg MS3Å/mmol substrate, 0.1 M substrate in PhCH3.
[b]
Measured by 1H NMR.
[c]
Measured by chiral HPLC. See Supporting Information for details.
[d]
Conducted at 50 °C.
[e]
Conducted at 45 °C.