Silver Selenide as the Novel Catalytic Material for Alcohol Oxidation

Abstract

By calcining selenium powder and silver powder at 150 ℃ under N2 protection, the novel material silver selenide (Ag/Se) could be easily fabricated. It possessed very strong oxygen carrier features and could activate the molecular oxygen to achieve the catalytic oxidation reactions. In this work, the Ag/Se-catalyzed alcohol oxidation reactions were investigated to afford a novel clean method for the synthesis of carbonyls. It could be applied for the oxidation reactions of primary and secondary alcohols, and could catalyze the selective oxidation of primary alcohols to synthesize aldehydes in moderate yields. Ag/Se as the novel Se-containing catalytic material may be comprehensively applied in future and significantly pushes forward the development of the chemistry of Se catalysis.

Ag/Se‐Catalyzed Selective Epoxidation of β‐Ionone with Molecular Oxygen

“…It was found that although the reaction catalyzed by the mixture of silver and selenium with their molar ratio at 1 : 10 led to 5 in poor yield, the Ag/Se material that was prepared via the calcination of silver and selenium showed obviously better catalytic activity, and the reaction catalyzed by Ag/Se could produce 5 in 42 % yield (Scheme 2, Runs 4 vs. 3). The phenomena demonstrated that the combination of silver and selenium during the calcination process could promote their catalytic activities for oxidation reaction, which was in accordance with the literature report [16] …”

“…On the basis of the above experimental results as well as the literature reports, [16,21–26] a plausible mechanism was supposed (Scheme 4). First, selenium as a non‐metal element may lead to the low valent selenium species in Ag/Se [16] .…”

“…On the basis of the above experimental results as well as the literature reports, [16,21–26] a plausible mechanism was supposed (Scheme 4). First, selenium as a non‐metal element may lead to the low valent selenium species in Ag/Se [16] . Since there are lone‐pair electrons in Se, the rest non‐bonding Se may coordinate with the Ag + like N, O, S etc, reducing the activities of metal sites via the steric hindrance and the electron‐donating effects [21] .…”

“…Au@C yolk‐in‐shell materials could also catalyze the epoxidation of β ‐ionone with O 2 , but the high cost of gold might impede the application of the technology in practical applications [15] . Ag/Se is an relatively cheap material that can be easily prepared via the calcination of selenium and silver powders [16] . Recently, we found that it could catalyze the epoxidation reaction of β ‐ionone using O 2 as oxidant free of any additives.…”

Preparation of quinazolinones using biosynthesized silver nanoparticles

“…We also report the green synthesis of silver nanoparticles (Ag NPs) using Echium amoenum ( E. amoenum ) extract. Recently, silver nanoparticles have been used as a suitable catalyst in many reactions, including the oxidation of alcohol, 21 oxidation of styrene, 22 synthesis of β-enaminones, 23 preparation of tetrazoles, 24 oxidation of phenylsilanes to silanols 25 and synthesis of propargylamines. 26 We found that our Ag NPs produce our desired compounds in high yields (80–97%) with excellent recovery and a simple work-up procedure.…”