14 / 57
Notes:
Volume 3, Issue 2 (Suppl)
Trends in Green chem
ISSN: 2471-9889
Environmental & Green Chemistry 2017
July 24-26, 2017
Page 32
5
th
International Conference on
6
th
International Conference on
July 24-26, 2017 Rome, Italy
Environmental Chemistry and Engineering
Green Chemistry and Technology
&
Catalytic activity and recyclability of polymer supported palladium or nickel nanoparticles in organic
reactions in water
Maria Michela Dell’Anna
1
, Matilda Mali
1
, Giuseppe Romanazzi
1
, Antonino Rizzuti
1
, Cristina Leonelli
2
and
Piero Mastrorilli
1
1
Polytechnic University of Bari, Italy
2
University of Modena and Reggio Emilia, Italy
A
n insoluble palladium catalyst (
Pd-pol
) was obtained by copolymerization of the metal containing monomer Pd(AAEMA)2
[AAEMA− = deprotonated form of 2-(acetoacetoxy)ethyl methacrylate] with ethyl methacrylate (co-monomer) and ethylene
glycol dimethacrylate (cross-linker), followed by
in situ
reduction of Pd(II) to Pd(0), to give polymer stabilized metal nanoparticles.
The good swellability in water exhibited by
Pd-pol
rendered it an ideal potential catalyst for reactions carried out in a green solvent,
such as water, since the migration of the reagents to the active sites would not be hampered by the solid support. With the aim to
develop innovative catalytic processes that enable chemical transformations to be performed under mild and sustainable conditions
with high efficiency, we decided to evaluate the catalytic activity of
Pd-pol
for several important organic reactions using water as
solvent.
Pd-pol
resulted highly active and selective in catalyzing (figure 1): the Suzuki-Miyaura coupling between aryl bromides
or activated aryl chlorides and phenylboronic acid; the oxidation of benzyl alcohols to aldehydes; the reduction of quinolines and
nitroarenes by H
2
or NaBH
4
.
Pd-pol
was recyclable for several consecutive runs (for example, at least 12 times in the nitroarene
reduction). TEM analyses carried out on the catalyst showed that the active species were supported palladium nanoparticles having
a mean size of 4 nm, which did not aggregate with the recycles. Recently, due to their low cost, Ni catalysts have been employed
in several organic reactions (mainly hydrogenations). In this context, we synthetized a Ni catalyst similar to
Pd-pol
, starting from
Ni(AAEMA)
2
and we employed it as active and recyclable, insoluble catalyst for the reduction of different nitroarenes to give the
corresponding anilines, under sustainable conditions. All these results proved that the proposed Pd or Ni based composite materials
are excellent hybrid structures as efficient and reusable catalysts.
Biography
Maria Michela Dell’Anna completed her PhD in “Chemistry of materials for special uses” at University of Reggio Calabria (Italy), giving a dissertation on “Synthesis
and characterization of new transition metal complexes: Aerobic oxidation of organic substrates and C-C bond forming reactions”. During her PhD studies, she
joined for one year the research group of Prof. M Cowie in the Chemistry Department of University of Alberta (Canada), where she worked on the synthesis and
characterization of bimetallic complexes. Since 2000, she has been Assistant Professor in Chemistry at Polytechnic of Bari. Since 2012 she has been the Editor
of the journal
Recyclable Catalysis
, merged with the journal
Catalysis for Sustainable Energy
. Her research interests are focused on: i) polymer supported metal
catalysts; ii) green nanocatalysis; iii) platinum complexes and iv) risk assessment. She is co-author of almost 45 publications in major journals and more than 20
communications in congresses.
mariamichela.dellanna@poliba.itMaria Michela Dell’Anna et al., Trends in Green chem, 3:2
DOI: 10.21767/2471-9889-C1-002