IJSRST17337 | Received : 01 March-2017 | Accepted : 08- March -2017 | March-April - 2017 [(3)2: 05-11 ]
© 2017 IJSRST | Volume 3 | Issue 3 | Print ISSN: 2395-6011 | Online ISSN: 2395-602X
Themed Section: Science and Technology
5
Synthetic Nitrogen-containing Polymers and their
Application as Copper Supports in Click Chemistry
Hallan Bruno de Matos Angeira Gomes
1
, Cristiane Aragão de Souza Bastardis
1
, Thays Pontes de Freitas
1
, Pedro Ivo
Canesso Guimarães,
1
Ayres Guimarães Dias,*
1
Jorge Luiz de Oliveira Domingos
*1
*
1
Lab. de Química Orgânica, Instituto de Química, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
jlo.domingos@gmail.com
1
ABSTRACT
Two nitrogen-containing polymers were synthesized and used as support for CuSO
4
to evaluate their catalytic
activity in 1,3-heterodipolar cycloaddition reactions (1,3-DC) of benzylazide and ethyl propiolate.
Polyvinylimidazole (PVI-DVB) was obtained by vinylimidazole polymerization with divinylbenzene and polystyryl
pyridine (PSP) was prepared by condensation of lutidine and terephtaldehyde and with collidine as the reticulating
agent. The activity was measured by titration with staNdard HCl solution, and PVI-DVB showed 4.6 mEg/g and
PSP 0.7 mEg/g polymer. Impregnation with copper was possible by stirring the polymers in aqueous CuSO
4
solution. PSP fixed less copper (~0.2 %) than PVI-DVB that fixed thirty times more (6.2 %). The 1,3-DC under
microwave irradiation, in the presence of PSP-Cu or PVI-DVB-Cu, gave origin to quantitative yields of the
triazoles, and 1,4 regioisomer was the main product. By reusing the copper supported (4X), no changes in yields
were observed, only a small decrease in regioselectivity.
Keywords: Polyvinylimidazole Divinylbenzene, Polystyryl Pyridine, Copper Supported, Click Chemistry
I. INTRODUCTION
The methodology of ‘solid phase’ synthesis was first
described in the literature by Merrifield and since then
the use of this approach in organic preparations has
expanded from laboratorial protocols to industrial
processes.
1
Solid supported reagents are easily removed from
reactions by filtration and recycling of recovered
reagents is economical, environment-friendly and
efficient.
Metal supported polymers have been successfully
employed in various catalytic processes and the presence
of heterochain polymers containing functional groups of
electron pair donors, such as carboxyl, hydroxyl, amino
derivative groups, sulfur and phosphorus can be used to
attach metals onto the surface of polymers.
2
Nitrogen-
containing heterocyclic compounds are an important
class of metal ligands and polymers containing these
groups have been used as a support in the preparation of
organic catalysts. Polyvinylpyridines (PVPY)
3
and poly-
N-vinylimidazole (PVI)
4
are the most representative
members of this group.
PVPY are interesting polymer ligands which can act as
catalytic supports and the presence of nitrogen atoms in
different positions in relation to the main chain affects
their complexing ability and hence, should influence
their catalytic activity.
3
Kureshy et al. studied supported
manganese salen complexes on 4-vinylpyridine
reticulated with DVB and described as a powerful
catalyst in the enantioselective epoxidation of styrene.
5
Spinelli et al. reported the ability of poly(4-
vinylpyridine) films to protect copper corrosion at acid
pH. These films managed to impart a significant level of
corrosion resistance to the copper samples and almost
100% efficiency was reached employing this
methodology.
6
PVI was used by Breslow et al. as an enzyme mimetic in