Table 1.
Conditions Screening a.
| Entry | Fe (x mol%) | Ln (y mol%) | Additives | Solvent | T °C | t/h | conv. (%) b | er (%) c |
|---|---|---|---|---|---|---|---|---|
| 1 | Fe(ClO4)2 (5.0) | L1(5.0) | - | MeOH | 30 | 28.5 | - | n.d. f |
| 2 | Fe(ClO4)2 (5.0) | L1 (5.0) | - | DCE | 30 | 28.5 | 57 d | 73:27 |
| 3 | Fe(ClO4)2 (5.0) | L1 (5.0) | - | CHCl3 | 30 | 28.5 | 68 d | 77:23 |
| 4 | Fe(ClO4)2 (5.0) | L1 (5.0) | - | toluene | 30 | 28.5 | 22 d | 80:20 |
| 5 | Fe(ClO4)2 (5.0) | L1 (5.0) | - | PhCl | 30 | 28.5 | 53 d | 79:21 |
| 6 | Fe(ClO4)2 (5.0) | L1 (5.0) | MS 4Å | PhCl | 30 | 5.0 | 12 d | 80:20 |
| 7 | Fe(ClO4)2 (5.0) | L1 (5.0) | MS 4Å | PhCl | 50 | 5.0 | 39 d | 78:22 |
| 8 | Fe(ClO4)2 (5.0) | L1 (5.0) | MS 4Å | PhCl | 70 | 5.0 | 38 d | 73:27 |
| 9 | Fe(ClO4)2 (5.0) | L1 (5.0) | MS 4Å | PhCl | 90 | 5.0 | 28 d | 70:30 |
| 10 | Fe(ClO4)3 (5.0) | L1 (5.0) | MS 4Å | PhCl | 50 | 5.0 | 76 | 76:24 |
| 11 | Fe(OAc)2 (5.0) | L1 (5.0) | MS 4Å | PhCl | 50 | 5.0 | 16 | n.d. f |
| 12 | Fe(OTf)2 (5.0) | L1 (5.0) | MS 4Å | PhCl | 50 | 5.0 | 19 | n.d. f |
| 13 | Fe(acac)2 (5.0) | L1 (5.0) | MS 4Å | PhCl | 50 | 5.0 | 23 | n.d. f |
| 14 | FeCl2 (5.0) | L1 (5.0) | MS 4Å | PhCl | 50 | 5.0 | 20 | n.d. f |
| 15 | Fe(ClO4)2 (7.5) | L1 (5.0) | MS 4Å | PhCl | 50 | 5.0 | 78 | 77:23 |
| 16 | Fe(ClO4)2 (10.0) | L1 (5.0) | MS 4Å | PhCl | 50 | 5.0 | 88(84 e) | 80:20 |
| 17 | Fe(ClO4)2 (12.5) | L1 (5.0) | MS 4Å | PhCl | 50 | 5.0 | 95 | 72:28 |
| 18 | Fe(ClO4)2 (5.0) | L1 (10.0) | MS 4Å | PhCl | 50 | 5.0 | 39 | 77:23 |
| 19 | Fe(ClO4)2 (10.0) | L1 (10.0) | MS 4Å | PhCl | 50 | 5.0 | 86 | 77:23 |
| 20 | Fe(ClO4)2 (10.0) | L2 (5.0) | MS 4Å | PhCl | 50 | 5.0 | 90 | 70:30 |
| 21 | Fe(ClO4)2 (10.0) | L3 (5.0) | MS 4Å | PhCl | 50 | 5.0 | 85 | 60:40 |
| 22 | Fe(ClO4)2 (10.0) | L4 (5.0) | MS 4Å | PhCl | 50 | 5.0 | 53 e | 78:22 |
| 23 | Fe(ClO4)2 (10.0) | L5 (5.0) | MS 4Å | PhCl | 50 | 5.0 | 67 e | 55:45 |
| 24 | Fe(ClO4)2 (10.0) | L6 (5.0) | MS 4Å | PhCl | 50 | 5.0 | - | n.d. f |
| 25 | Fe(ClO4)2 (10.0) | L7 (5.0) | MS 4Å | PhCl | 50 | 5.0 | - | n.d. f |
| 26 | Fe(ClO4)2 (10.0) | L8 (5.0) | MS 4Å | PhCl | 50 | 5.0 | - | n.d. f |
a All reactions carried out with 1a (0.5 mmol), MS 4Å (150 mg) in 5 mL solvent under O2 atmosphere (1 atm). b Conversions determined by GC using dodecane as an internal standard. c Determined by HPLC (Chiralpak AS-H). d Determined by 1H-NMR analysis. e Isolated yield. f n.d.: not detected.