Table 2.
Scope of the visible-light photoredox catalyzed synthesis of 2,5-diaryl-1,5-dienes 1.
| ||
|---|---|---|
| Entry | R | Product (Yield in %)a |
| 1 | H (2a) | 1a (81%, 80%b) |
| 2 | 4-Cl (2b) | 1b (80%) |
| 3 | 4-Br (2c) | 1c (82%) |
| 4 | 3-Br (2d) | 1d (84%, 79%b) |
| 5 | 2-F (2e) | 1e (66%)c |
| 6 | 4-Me (2f) | 1f (79%)d |
| 7 | 3-Me (2g) | 1g (85%)d |
| 8 | 2-Me (2h) | 1h (71%e, 69%f) |
| 9 | 4-OMe (2i) | 1i (59%) |
| 10 | 3-OMe (2j) | 1j (72%) |
| 11 | 2-OMe (2k) | 1k (67%)g |
| 12 | 4-CN (2l) | 1l (70%) |
| 13 | 3-CN (2m) | 1m (70%)d |
Isolated yield of 1 after silica gel chromatography (average of two experiments).
1.0 mmol scale.
26% recovered SM 2e (89% brsm).
CH2Cl2 (0.2 M).
29% recovered SM 2h (quant. brsm).
1.0 mmol scale, 25% recovered SM 2h (91% brsm).
Ru(bpy)3(PF6)2 (1.5 mol%), 42 h reaction time, 18% recovered SM 2k (81% brsm).