Table 1 Optimization of the reaction conditionsa
Entry | Additive | [Pd] | Base | Solvent | Yield% | Ee% |
---|---|---|---|---|---|---|
1 | H2O | [Pd(allyl)Cl]2 | NaOtBu | Et2O/Hexane = 1:1 | 74 | 92 |
2 | -- | [Pd(allyl)Cl]2 | NaOtBu | Et2O/Hexane = 1:1 | 84 | 84 |
3 | 4 Å MS | [Pd(allyl)Cl]2 | NaOtBu | Et2O/Hexane = 1:1 | 79 | 91 |
4 | MeOH | [Pd(allyl)Cl]2 | NaOtBu | Et2O/Hexane = 1:1 | 75 | 79 |
5 | EtOH | [Pd(allyl)Cl]2 | NaOtBu | Et2O/Hexane = 1:1 | 54 | 70 |
6 | iPrOH | [Pd(allyl)Cl]2 | NaOtBu | Et2O/Hexane = 1:1 | 52 | 60 |
7 | H2O | Pd(dba)2 | NaOtBu | Et2O/Hexane = 1:1 | 43 | 93 |
8 | H2O | Pd(OAc)2 | NaOtBu | Et2O/Hexane = 1:1 | 72 | 92 |
9 | H2O | PdCl2 | NaOtBu | Et2O/Hexane = 1:1 | 12 | 78 |
10 | H2O | [Pd(allyl)Cl]2 | KOtBu | Et2O/Hexane = 1:1 | – | – |
11 | H2O | [Pd(allyl)Cl]2 | LiOtBu | Et2O/Hexane = 1:1 | 41 | 7 |
12 | H2O | [Pd(allyl)Cl]2 | Cs2CO3 | Et2O/Hexane = 1:1 | 15 | 85 |
13 | H2O | [Pd(allyl)Cl]2 | NaOH | Et2O/Hexane = 1:1 | 29 | 97 |
14 | H2O | [Pd(allyl)Cl]2 | NaOtBu | Toluene | 90 | 91 |
15 | H2O | [Pd(allyl)Cl]2 | NaOtBu | THF | 51 | 90 |
16 | H2O | [Pd(allyl)Cl]2 | NaOtBu | Et2O | 36 | 94 |
17 | H2O | [Pd(allyl)Cl]2 | NaOtBu | Hexane | 55 | 88 |