| Entry | [H] | Solvent | Temperature (˚C) | Time (hr) | aYield (%) | bRatio 7:8:9 |
| 1 | NaBH4 | Ether | 0 | 24 | 90.4 | 24:1:0 |
| 2 | NaBH4 | Methanol | 0 | 24 | 97.0 | 17:1:0 |
| 3 | LiAlH4 | Ether | 25 | 24 | 69.0 | 6:1:0 |
| 4 | Al(O-i-Pr)3 | Toluene | Reflux | 24 | 87.5 | 1:2:11c |
| 5 | N(CH3)4BH4 | Methanol | 25 | 12 | 97.0 | 25:1:0 |
| 6 | Selectride | THF | 25 | 24 | 98.0 | 20:1:0 |
| 7 | BH3S(CH3)2 | CH2Cl2 | 25 | 72 | 70.0 | 15:1:0 |