4 FLP-Mediated C–H-Activation
137
R 3 P
E(C 6 F 5 ) 3
R = o-tol
R = tBu
Ph
+
Ph
E(C 6 F 5 ) 3 [tBu 3 PH]
Ph
(otol) 3 P
H
E(C 6 F 5 ) 3
E = B, Al
H
4
5
Scheme 4.27 Reaction of intermolecular FLPs with terminal alkynes
Mes 2 P
B(C 6 F 5 ) 2
C 3 H 7
rt, pentane
Mes 2 HP
(C 6 F 5 ) 2
B
C 3 H 7
7
H
6
Scheme 4.28 Reaction of intramolecular FLPs with terminal alkynes
B(C 6 F 5 ) 3
B(C 6 F 5 ) 3
B(C 6 F 5 ) 3
H
H
H
H
H
[Hbase]
H
B(C 6 F 5 ) 3
H
base
H
B(C 6 F 5 ) 3
(C 6 F 5 ) 3 B
[Hbase]
H
C 6 F 5
(C 6 F 5 ) 2 B
B(C 6 F 5 ) 3
[Hbase]
0%
90%
100%
100%
10%
0%
tBu 3 P
N
H
N
Me
Me
8
9
8
9
base
base
Wagner-Meerwein-type
Rearrangement
Int33
Int34
Int35
Scheme 4.29 Proposed reaction pathways between acetylene and B(C 6 F 5 ) 3 with different bases