عنوان
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Silica vanadic acid [SiO2–VO(OH)2] as an efficient
heterogeneous catalyst for the synthesis of 1,2-
dihydro-1-aryl-3H-naphth[1,2-e][1,3]oxazin-3-one
and 2,4,6-triarylpyridine derivatives via anomeric
based oxidation†
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چکیده
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Silica-bonded vanadic acid [SiO2–VO(OH)2] (SVA) efficiently catalyzed the synthesis of 1,2-dihydro-1-aryl-
3H-naphth[1,2-e][1,3]oxazin-3-ones via reacting aromatic aldehydes and b-naphthol and urea under
solvent-free condition. Additionally, 2,4,6-triarylpyridine derivatives were prepared through the
condensation of ammonium acetate, aromatic aldehyde and various acetophenone in the presence of
a catalytic amount of [SiO2–VO(OH)2] (SVA) under a same condition. A new anomeric based oxidation
was proposed for the final step of the 2,4,6-triarylpyridine derivatives synthesis which was supported by
theoretical studies. So the described new mechanistic approach can open up a new and promising
insight in the course of rational design, synthesis and applications of novel hydride releasing compounds.
The significant features of the present procedure are short reaction time, high yields, easy work-up, and
recyclability of the SVA catalyst.
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