| In this paper,several solid-supported(diacetoxyiodo)benzenes were prepared, their structure was verified by FT-IR and the loading of hypervalent iodine was calculated based on iodometric titration.These solid-supported hypervalent iodine reagents could be applied for oxidation of alcohols and synthesis of benzoxazoles, additionally,these solid species could be recovered and regenerated and reused.The main results are summarized as follows:1.A novel polystyrene-graft-G2.0 diethanolamine-typed dendrimer-supported (diacetoxyiodo)benzene reagent was prepared,and its activity as oxidant was examined.The loading of hypervalent iodine was 1.17 mmol/g.As dendrimers have good swelling property in water,this polymer-supported hypervalent iodine reagent was found very effective for the oxidation of primary and secondary alcohols to the corresponding aldehydes and keones in water,and it could be recycled for 3 times without significant loss of activity.2.A novel magnetic nanoparticle-supported(diacetoxyiodo)benzene was prepared for the first time,and its activity as oxidant was examined.The loading of hypervalent iodine was 0.25 mmol/g.It was found that this magnetic nanoparticle-supported hypervalent iodine reagent could effect the oxidation of primary alcohols and secondary alcohols to the corresponding aldehydes and keones in the presence of KBr in water,and the magnetic nanoparticle-supported oxidant could be easily recovered by magnetic separation and reoxidized after the reaction,the results demonstrated that the oxidant could be recycled 3 times without losing its activity.3.A novel polystyrene-supported(diacetoxyiodo)benzene reagent was prepared, the loading of hypervalent iodine was 1.70 mmol/g.This polymer-supported hypervalent iodine reagent as oxidative reagent could be applied for facile synthesis of benzoxazoles in yield 63-94%,and it could be easily recovered and recycled for 5 times without loss of activity.
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