8 Earth-Abundant d-Block Metal Nanocatalysis for Coupling …
271
[Cu 2 O NPs] (2.5% mol)
100 °C, 2 h
glycerol
N 3
R
+
N
N N
R
R = Ph, Cy, n-Bu, t-Bu, (CH 2 ) 3 -CH 2 -OH, CH 2 CH 2 -OH,
(CH 3 ) 2 C-OH, (CH 2 ) 5 -CH 2 OH, CH 2 -NMe 2 ,
Isolated Yield: 91-97%
Scheme 8.17 Cu 2 O NPs catalyzed azide–alkyne cycloaddition in glycerol [24]
O
Cl
NaN 3
+
+
N
N
120 ºC, 6 h
PEG300
[Cu 2 O NPs] (5 mol%)
Isolated Yield: 82-91%
R = 4-Me, 3-Me, 4-MeO, 3-MeO, 4-Me 2 N, 3,4-Me
NH 2
R
R
Scheme 8.18 Cu 2 O nanoparticles catalyzed the synthesis of 2H-indazoles [115]
Scheme 8.19 CuNPs
stabilized by chitosan
applied in C–S couplings
[49] (CS stands for chitosan)
SH
X
R
+
S
Y
[Cu-CS] (2 mol%)
toluene
Et 3 N
130 ºC, 60 h
X = Br, I
R = NO 2 , H, OMe
Yield: 84-96%
Fig. 8.10 SEM (left) and TEM (right) images of Cu(I) grafted to Fe 3 O 4 modified by isonicotinic
groups. Reprinted with permission from [53], Copyright 2019 Wiley, license no. 4640160235060
Scheme 8.20 Synthesis of
phenols catalyzed by
Cu-based catalyst supported
on modified Fe 3 O 4 [53]
O
I
O
OH
2:1 PEG:H 2 O
130 ºC, 23 h
[Fe 3 O 4 @INH@Cu]
Isolated Yield: 90%