self-assembling complexation of a polymeric phosphine ligand and a Pd species at
the interface of two parallel laminar layers flowing through the microchannel. The
developed microchannel with a polymeric membrane containing an immobilized Pd
complex could be successfully used to perform a Suzuki–Miyaura coupling reaction.
In 2012, the same group found that a Pd complex immobilized on a polymeric
membrane in a microchannel could be reduced to form Pd nanoparticles
Fig. 7 Continuous oxidation using capillary-immobilized Au nanoparticle catalyst
a)
LiAlH 4 in THF
rt, 48 h
Polysiloxane
coated
capillary 3
1) wash
2) dry
O Si
O
Me
NH 2
n
m
NH 2
wall of channel
b)
Polymer with
cross-linking
moieties
1. NaBH 4 in diglyme-THF, rt
2. AuClPPh 3 , rt, 3 h
3. Cyclohexane
Microencapsulated
gold (MC-Au)
OH
O
O
OH
Au
NH 2
c)
Slow addition
50 ºC
N
H
OH
O
OH
OH
Au
170 ºC, 5 h
Au-immobilized capillary
Scheme 5 Immobilization of Au nanoparticles on surface-modified capillary
216
H. Miyamura and S. Kobayashi