Chemistry Reference
In-Depth Information
included catalysis of self-separating atom transfer radical polymerization [
28
], RCM catalysis [
29
],
and catalysis of a chromium-based polycarbonate polymerization [
30
]. It is important to note that these
polyisobutylene-supported catalysts exhibited close to or similar activity to their unanchored
counterparts. In addition, they were readily recovered and reused without appreciable loss of activity.
N
ยด
jera and coworkers [
34
] used a commercial poly(styrene-
-maleic anhydride) copolymer as
support material. The copolymer was first reacted with hydroxylamine and then converted to a
polymer-supported
alt
-hydroxy succinimide. The product was then used in a peptide-coupling
reactions. Low levels of racemization were reported. Addition of hexane allowed the removal of
the polymeric material by filtration.
N
O
O
OH
O
N
O
O
n
n
+
NH
2
OH
The polymeric imide could then be reacted with primary amines or ammonia to form ammonium
salts for a subsequent reactions with a carboxylic acid in the presence of a coupling reagent. It could
then be converted to amides or functionalized as a uranium salt for use as polymer-supported peptide
coupling. In addition, the anhydride was also reacted with di(2-pyrldyl)methylamine and formed a
recoverable palladium catalyst for cross-coupling reactions that could take place in water.
N
N
O
O
O
O
N
O
NH
2
n
n
+
NN
Na
2
PdCl
4
Cl
Cl
Pd
N
N
O
N
O
n
