Table 1.
Ligand Screen
 | ||||||
|---|---|---|---|---|---|---|
| entry | [Rh(C2H4)2Cl2] | L* (mol %) | time (h) | 3: 4b | yield (%) of 3aac | ee(%) of 3aad |
| 1 | 5% | L1 (10) | 12 | 2.4: 1 | 40 | 84 |
| 2 | 5% | L2 (10) | 12 | 2.8: 1 | 57 | 94 |
| 3 | 3% | L3 (6) | 3 | 3.4: 1 | 64 | 95 |
| 4 | 3% | L4 (6) | 3 | 3.4: 1 | 70 | 97 |
| 5 | 3% | L5 (6) | 3 | 4.8: 1 | 78 | 89 |
a
Conditions: 1 (2 equiv), 2 (0.16 mmol), Rh catalyst, L in PhMe at 110 °C.
b
Product selectivity (3: 4) is determined by 1H NMR of the unpurified reaction mixture.
c
Isolated yield.
d
Determined by HPLC analysis using a chiral stationary phase.