TABLE 2.
Screening of Additivesa
| |||||
|---|---|---|---|---|---|
| entry | additive (equiv) | 3a (%) | entry | additive (equiv) | 3a (%) |
| 1 | none | 18 | 16 | HClc (1) | 22 |
| 2 | NaF (2) | 16 | 17 | LiCl (1) | 55 |
| 3 | KF (2) | 41 | 18 | NaCl (1) | 18 |
| 4 | CsF (2) | 28 | 19 | KCl (1) | 16 |
| 5 | TBAFb (2) | 11 | 20 | CsCl (1) | 34 |
| 6 | KTFA (1) | 33 | 21 | MgCl2 (1) | 51 |
| 7 | LiBF4 (1) | 17 | 22 | CaCl2 (1) | 25 |
| 8 | NaOAc (1) | 29 | 23 | BiCl3 (1) | 61 |
| 9 | KOAc (1) | 47 | 24 | CuCl2 (0.5) | 60 |
| 10 | CsOAc (1) | 28 | 25 | CuCl2 (1) | 73 |
| 11 | K2CO3 (1) | 34 | 26 | CuCl2 (2) | 81 |
| 12 | Cs2CO3 (1) | 17 | 27 | CuCl2 (3) | 81 |
| 13 | K3PO4 (1) | 31 | 28 | CuCl (2) | 31 |
| 14 | Me3CCO2H (1) | 16 | 29 | CuI (2) | 0 |
| 15 | TFA (0.1) | 31 | |||
Reaction conditions: 1 (1 equiv), 2a (2 equiv), Pd(OAc)2 (10 mol%), Cu(OAc)2 (2 equiv), DMF (0.2 M) under N2 for 20 h at 60 °C, the yield was determined by 1H NMR analysis of the crude product using Ph3,SiMe (1 equiv) as the internal standard.
1.0 M in THF.
12.1 M.