Table 2.
Selective reduction of ketones 6-9a to their corresponding enantioenriched alcohols 6-9b using baker’s yeast in different solvent conditions [38].
| Substrate | Solvent | Conversion (%) | ee (%) |
|---|---|---|---|
| 6a (a) | water | 88 | 96 (S) |
| 6a (a) | DES A (60% w/w) in water (c) | 31 | 78 (S) |
| 6a (a) | DES B (50% w/w) in water (d) | 88 | 88 (S) |
| 6a (a) | DES B (90% w/w) in water (d) | 36 | 96 (R) |
| 7a (b) | water | 82 | 94 (S) |
| 7a (b) | DES B (90% w/w) in water (d) | 10 | 90 (R) |
| 8a (b) | water | 90 | 98 (S) |
| 8a (b) | DES B (90% w/w) in water (d) | 15 | 40 (R) |
| 9a (b) | water | >95 | 2 (S) |
| 9a (b) | DES B (90% w/w) in water (d) | 12 | 24 (R) |
(a) Reaction conditions: ketone 6a (1.5 mM), baker’s yeast (230 mg/mL) at 37 °C. (b) Reaction conditions: ketones 7-9a (1.5 mM), baker’s yeast (200 mg/mL) at 37 °C. (c) DES A: ChCl:D-fructose (3:2 w/w). (d) DES B: ChCl:Gly (1:2 mol/mol).