MnI catalyzed β-methylation of 2a with CO and H2: influence of different reaction conditionsa.
| ||||||
|---|---|---|---|---|---|---|
| CO (bar) | H2 (bar) | Base (equiv.) | Temp. (°C) | Conv. (%) | Yield (%) | |
| 1b | 5 | 15 | NaOtBu (2) | 150 | >99 | 65 |
| 2 | 5 | 15 | NaOtBu (2) | 150 | >99 | 92 |
| 3 | 5 | 15 | NaOtBu (2) | 120 | 94 | 73 |
| 4 | 5 | 15 | NaOtBu (2) | 170 | >99 | 54 |
| 5 | 2.5 | 7.5 | NaOtBu (2) | 150 | 72 | 15 |
| 6 | 8 | 24 | NaOtBu (2) | 150 | >99 | 93 |
| 7 | 5 | 15 | NaOtBu (1) | 150 | 82 | 67 |
| 8 | 5 | 15 | KOtBu (2) | 150 | >99 | 0 |
| 9 | 5 | 15 | Cs2CO3 (1) | 150 | 8 | 0 |
a
Reaction conditions: 2-phenylethanol 2a (0.5 mmol), Mn-complex 1 (2 mol%), CO, H2, base, and toluene (0.8 mL) were heated in a high-pressure reactor for 24 h. Conversion and yield were calculated using 1H NMR spectroscopy.
b
Modified conditions: 2a (0.5 mmol), 1 (1 mol%), CO, H2, base, and toluene (0.8 mL) were heated in a high-pressure reactor for 24 h.