Table 1 Screening of the reaction conditions.

Reaction conditions: 1A (0.2 mmol), 2 (1.5 equiv.), and Cu(I) (10 mol %) under argon atmosphere. Conversion (c) and yield (y) were determined by 1H nuclear magnetic resonance (NMR) spectroscopy using CH2Br2 as an internal standard. 2 (1.2 equiv.) was added for entry 6. 2 (1.8 equiv.) was added for entry 7. 2 (2.4 equiv.) was added in two portions with a time interval of 10 hours for entry 15. EtOAc, ethyl acetate; DCE, 1,2-dichloroethane; THF, tetrahydrofuran.


Entry[Cu]SolventT (°C)Time (hours)c (%)y (%)
1CuIEtOAc80249055
2CuBrEtOAc80249546
3CuClEtOAc80249054
4CuOAcEtOAc802410055
5CuCNEtOAc80249058
6CuCNEtOAc80247034
7CuCNEtOAc802410052
8CuCNEtOAc60243020
9CuCNEtOAc80188561
10CuCNEtOAc1002410040
11CuCNDCE801810032
12CuCNCH3CN801810038
13CuCNTHF80184030
14CuCN1,4-Dioxane80187058
15CuCN1,4-Dioxane80209569