obtaining a large amount of aryl amines in good to excellent yields under very
smooth reaction conditions [141].
Phosphine-oxime L22 also proved to be a good ligand for the N-arylation of
alkyl amines and N-heterocycles (Scheme 8) [142]. Although product formation
takes place only in the case of aryl iodides and at higher temperatures (80
C) than in
earlier cited examples, the presence of a phosphorus atom in L22 constitutes an
interesting feature for mechanistic studies (
31 P NMR).
Wass et al. described another phosphorous-based ligand for the amidation
of aryl iodides [143]. The yields were only fair but several well-identified
Scheme 6 Copper iodide/L19 or L20-catalyzed reactions of alkyl amines or amino acids with
aryl iodides
examples
Scheme 7 Copper iodide/L6 or L7-catalyzed reactions of alkyl amines and anilines with aryl
halides
Cu 2 O (5%)
L22 (20%)
Cs 2 CO 3 (2 eq.)
L22
I
R
R
R = EWG or EDG
R
2
HN
> 30 examples
R
1 , R
2 = Alk
R
1
R
2
N
R
1
and N-heterocycles
CH 3 CN, 80 °C
N OH
P
O
Ph
Ph
Scheme 8 Copper(I) oxide/L22-catalyzed reactions of alkyl amines and N-heterocycles with aryl
iodides
Copper-Catalyzed C(aryl)–N Bond Formation
181