Catalysis Communications
Short Communication
Synthesis and characterization of SBA-polyperoxyacid: An efficient
heterogeneous solid peroxyacid catalyst for epoxidation of alkenes
Jamal Davarpanah, Ali Reza Kiasat 1
Chemistry Department, College of Science, Shahid Chamran University, Ahvaz 61357-4-3169, Iran
a r t i c l e i n f o
a b s t r a c t
Article history:
Received 8 October 2013
Received in revised form 21 November 2013
Accepted 23 November 2013
Available online 1 December 2013
SBA-propy-3-allyl-imidazolium chloride (SBA-Im-Allyl) was easily prepared by nucleophilic substitution of SBA-
propylchloride (SBA-Cl) with imidazole and then quaternization with allyl chloride. Then, a novel solid
polyperoxyacid was synthesized by anchoring and oxidation of polyacrylic acid onto the surface of SBA-Im-
Allyl. FT-IR, SEM, TGA–DTG and BET have been used to characterize the solid polyperoxyacid. This new catalyst
did not leach from the support and can be recycled by treatment with hydrogen peroxide solution, and also
loading of the catalyst was measured by iodometric titration. The solid polyperoxyacid shows efficient catalytic
activity toward epoxidation of alkenes.
Keywords:
Organic–inorganic hybrid silica
Epoxidation of alkenes
Solid peroxyacid
© 2013 Elsevier B.V. All rights reserved.
Imidazolium salt
1. Introduction
low grafting amount of active sites, high mass-transfer resistance and
poor catalytic activities [11]. To elevate the grafting amount, the prepa-
Epoxidation of alkenes is a very useful reaction in industrial organic
synthesis since the epoxides are key raw materials for the synthesis of
fine chemicals and modern industrial process [1]. The most widely
used method for epoxidation is the use of hydrogen peroxide as oxidant.
Reactions with H2O2 generally require the presence of a catalyst [2]. In
spite of considerable research efforts during the last decades, only a
few useful catalytic systems for epoxidation with H2O2 have been devel-
oped. These include tungsten [3,4], manganese [5,6], and rhenium [7,8]
based systems. An alternative is the epoxidation with peracids, which
generally has some certain drawbacks, such as high price, risk of uncon-
trolled decomposition, and the formation of 1 equivalent of carboxylic
acid as a byproduct [9]. These drawbacks might be overcome if a suit-
able catalyst is adopted into the reaction system. Consequently, the de-
velopment of solid peroxyacid catalysts is expected to have a major
impact in industrial applications as well as for scientific aspects. Sup-
ported organic peroxyacids are interesting alternatives for the oxygen-
ation of organic substrates. Immobilization of peroxyacids on solid
supports and their conversion to insoluble polymeric derivatives have
been suggested as alternative ways of getting around the problems.
Using these strategies, simplifies both the isolation of the reaction prod-
ucts and reagent recycling by suppressing neutralization and extraction
operations for the separation of the carboxylic acid formed in the
oxygen transfer step [10].
ration and application of mesoporous materials for such applications
have become an intensively study in heterogeneous catalysis. SBA-15
has attracted a great deal of recent interest because of its tunable pore
sizes (5–30 nm), well-organized array of straight channel, high surface
area, open pore structure and narrow pore size distribution and shape
selectivity, and also because of its thick pore walls, around 4 nm,
which provide enhanced mechanical stability [12]. Unlike traditional
inorganic materials, SBA-15 is typically synthesized under mild condi-
tions, allowing for the incorporation of constituent building blocks
with desired functionalities, leading to numerous functional SBA-15
that has shown promise for a number of applications, such as petroleum
refining, medicinal applications, separations, catalysis, pollutant remov-
al and sensors [13–17].
Considering these facts and taking into account all these, we decided
to synthesis a novel supported peroxyacid catalyst on SBA-15, using
polymerization of acrylic acid and then oxidation of carboxylic to
peroxyacid groups. These multi-layered catalysts are synthesized by
several steps including polymerization of acrylic acid and surface
functionalization of SBA-15. The catalytic activity of the synthesized
catalyst was investigated for the epoxidation of alkenes (Scheme 1).
2. Experimental
Silica is usually used as support due to its easy availability and low
cost. However, the wide-range pore distribution, irregular pore shape,
low pore volume and low specific surface area of silica often lead to
2.1. General
Tetraethylorthosilicate (TEOS), 3-chloropropyltrimethoxysilane
(CPTMS) and Pluronic P123 triblock copolymer (EO20PO70EO20, MW.
5800) were supplied by Aldrich. Other chemical materials were pur-
chased from Fluka and Merck companies and used without further
1
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