Table 1.
Optimization of the rhoda‐electrocatalyzed domino C−H activation.[a]
|
Entry |
Base |
Additive |
Solv. |
I [mA] |
t [h] |
3 aa [%] |
|---|---|---|---|---|---|---|
|
1 |
KOAc |
– |
MeOH |
4.0 |
10 |
38 |
|
2 |
KOAc |
– |
TFE |
4.0 |
10 |
0 |
|
3 |
KOAc |
– |
H2O |
4.0 |
10 |
0 |
|
4 |
KOAc |
– |
MeCN |
4.0 |
10 |
0 |
|
5 |
KOAc |
– |
EtOH |
4.0 |
10 |
4 |
|
6 |
NaOAc |
– |
MeOH |
4.0 |
10 |
25 |
|
7 |
NaOPiv |
– |
MeOH |
4.0 |
10 |
29 |
|
8 |
CsOAc |
– |
MeOH |
4.0 |
10 |
9 |
|
9 |
KOAc |
PivOH |
MeOH |
4.0 |
10 |
43 |
|
10 |
KOAc |
AdOH |
MeOH |
4.0 |
10 |
46 |
|
11 |
KOAc |
AcOH |
MeOH |
4.0 |
10 |
43 |
|
12 |
KOAc |
AdOH |
MeOH |
4.0 |
6 |
56 |
|
13 |
KOAc |
AdOH |
MeOH |
2.0 |
12 |
75 |
|
14 |
KOAc |
AdOH |
MeOH |
2.0 |
12 |
90[b] |
|
15 |
KOAc |
AdOH |
MeOH |
2.0 |
12 |
89[c] |
|
16 |
KOAc |
AdOH |
MeOH |
– |
12 |
trace[d] |
|
17 |
KOAc |
AdOH |
MeOH |
2.0 |
12 |
0[e] |
|
18 |
KOAc |
AdOH |
MeOH |
2.0 |
12 |
60[f] |
[a] Undivided cell, graphite felt anode (GF) (10×15×6 mm3), platinum plate cathode (Pt) (10×15×0.25 mm3), 1 a (0.2 mmol), 2 a (0.7 mmol), [Cp*RhCl2]2 (2.5 mol %), base (2.0 equiv), additive (0.1 equiv), solvent (4.0 mL), 25 °C under air, yield of isolated product. [b] RhCp*(CH3CN)3(SbF6)2 (5.0 mol %), 35 °C. [c] RhCp*(CH3CN)3(SbF6)2 (2.5 mol %), 35 °C. [d] RhCp*(CH3CN)3(SbF6)2 (5.0 mol %), without electricity, 35 °C. [e] Without rhodium catalyst, 35 °C. [f] RhCp*(CH3CN)3(SbF6)2 (2.5 mol %), 35 °C, under N2.