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green solvents in these reactions and also the use of vanillin
in the synthesis of the catalyst make these reactions interest-
ing from environmental and economic points of view. More
importantly, this catalyst can be reused several times without
loss of its catalytic activity.
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FIGURE 7 Recycling test for oxidation of methylphenyl sulfide under
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4
| CONCLUSIONS
In summary, we have developed a recyclable Cu(II) complex
immobilized on MCM‐41 nanoparticles to catalyse the
synthesis of symmetric diaryl sulfides and 5‐substituted
1H–tetrazoles and selective H2O2 (30%) oxidation of organic
sulfides to sulfoxides under mild reaction condition. The use
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