Table 1. Heteroarylation of 3 with 4.
| ||
Entry | Change from the standard conditions, reagents (equiv.) | Yield of 4a a (%) |
1 | Standard conditions | 84 (80 b ) |
2 | 2 → Bl-OAc 1 | 25 |
3 | 2 → Bl-OH 5 | 3 |
4 | 2 → PFBl-OAc 6 | 30 |
5 | 2 → PhI(OTFA)27 | 4 |
6 | 2 → PhI(OTFA)27 (2.3), CFL → blue (LED, 100 W), HFIP → CH2Cl2, no Ru(bpy)3Cl2 | 3 |
7 | 2 → PhI(OAc)2 | 28 |
8 | Ru(bpy)3Cl2 (0.5 → 1 mol%) | 61 |
9 | Ru(bpy)3Cl2 → Ir(ppy)3 | 13 |
10 | Ru(bpy)3Cl2 → [Ir(dF(CF3)ppy)2(dtbpy)]PF6 | 32 |
11 | No Ru(bpy)3Cl2 | <1 |
12 | HFIP → CH2Cl2 | 3 |
13 | HFIP → CF3CH2OH | 38 |
14 | HFIP → HFIP/CH2Cl2 (1/5) | 8 |
15 | 3 (1.5 → 1) | 42 |
16 | 3 (1.5 → 2) | 86 |
17 | 2 (1.35 → 1.5) | 70 |
18 | 2 (1.35 → 1.2) | 63 |
aNMR yield.
bIsolated yield on a 0.4 mmol scale.