4 FLP-Mediated C–H-Activation
159
N 2 O
Al(C 6 F 5 ) 3
R 3 P
R 3 P
O
Al(C 6 F 5 ) 3
Al(C 6 F 5 ) 3
- dibenzyl
Mes 3 P HO
Al(C 6 F 5 ) 3
Al(C 6 F 5 ) 3
R = Mes
PhMe
R = Nap
PhBr
R = Nap
PhMe
Nap 3 P HO
Al(C 6 F 5 ) 3
Al(C 6 F 5 ) 3
Bn
Nap 3 P HO
Al(C 6 F 5 ) 3
Al(C 6 F 5 ) 3
Br
Scheme 4.52 Activation of arenes using frustrated Lewis radicals
OR
2
O
R
1
R
3
R
3
B(C 6 F 5 ) 3 (1 equiv.)
Mes 3 P (1 equiv.)
66 °C, 7 h
THF (0.2 M)
+
R
5
R
5
R
4
R
2
R
4
R
2
R
5 : H, F , OMe
Me
R
3
R
6 : 4-H, 3-Me,
4-Me, 4-t Bu,
4-F, 4-Cl, 4-Ph
R
6
R
4
H
Me
35 examples
Scheme 4.53 Scope of the radical Heck reaction promoted by frustrated radical pairs
4.9 Concluding Remarks
While the C–H functionalization using TMs has been extensively studied by several
research groups over the past two decades, leading to several high impact transformations, very few FLP systems have been reported to do these catalytic transformations.
159
N 2 O
Al(C 6 F 5 ) 3
R 3 P
R 3 P
O
Al(C 6 F 5 ) 3
Al(C 6 F 5 ) 3
- dibenzyl
Mes 3 P HO
Al(C 6 F 5 ) 3
Al(C 6 F 5 ) 3
R = Mes
PhMe
R = Nap
PhBr
R = Nap
PhMe
Nap 3 P HO
Al(C 6 F 5 ) 3
Al(C 6 F 5 ) 3
Bn
Nap 3 P HO
Al(C 6 F 5 ) 3
Al(C 6 F 5 ) 3
Br
Scheme 4.52 Activation of arenes using frustrated Lewis radicals
OR
2
O
R
1
R
3
R
3
B(C 6 F 5 ) 3 (1 equiv.)
Mes 3 P (1 equiv.)
66 °C, 7 h
THF (0.2 M)
+
R
5
R
5
R
4
R
2
R
4
R
2
R
5 : H, F , OMe
Me
R
3
R
6 : 4-H, 3-Me,
4-Me, 4-t Bu,
4-F, 4-Cl, 4-Ph
R
6
R
4
H
Me
35 examples
Scheme 4.53 Scope of the radical Heck reaction promoted by frustrated radical pairs
4.9 Concluding Remarks
While the C–H functionalization using TMs has been extensively studied by several
research groups over the past two decades, leading to several high impact transformations, very few FLP systems have been reported to do these catalytic transformations.