Antimony selenide (Sb2Se3) is a low-toxic, element-abundant, narrow bandgap (Eg = ∼1.1–1.3 eV) semiconductor that shows potential for UV-Visible-Near-infrared optoelectronic applications. This paper reports the use of potassium selenocyanate (KSeCN) as a novel molecular selenium source to synthesize Sb2Se3 uniform nanorods. The resulting nanorods have been carefully characterized and are found to exhibit decent photoconductivity as well as broad-spectrum optical absorption with an Eg value of ∼1.35 eV. A molecular reaction mechanism is rationally proposed and evidenced for forming Sb2Se3, which is related to the thermal decomposition of selenocyanate (SeCN−) anions through the cleaving of Se–CN bonds to elemental Se(0), followed by its reduction to Se2− anions. Our work using KSeCN offers an alternative method for the synthesis of metal selenides with desirable nanostructures and properties.
A simple, exogenous-base-free, and NBS-mediated C-selenocyanation/cyclization reaction of enaminones with KSeCN under mild conditions, providing a facile route to 2-aminoselenazole products, has been developed. This efficient protocol is postulated to first undergo the NBS-oxidated polarity reversal of the reactive SeCN- anion to form N-selenocyanosuccinimide as an electrophilic selenium source, which can induce the C-selenocyanation of enaminones and enamino esters, followed by a nucleophilic cyclization promoted by in-situ yielded HBr.
Jie Zhu,Baojun Xu,Jingjing Yu,Yaokun Ren,Jin Wang,Ping Xie,Charles U. Pittman,Aihua Zhou
Flavone selenide or sulfur-containing derivatives are pretty valuable in drug discovery due to their diversity of important bioactivities. Here, two simple Cu-catalyzed methods of constructing C–Se and C–S bonds on flavone skeletal structures via C–H functionalization are reported, which regioselectively afford flavone selenide and sulfide derivatives in good yields using cheap KSeCN or KSCN salts as selenium and sulfur agents. These methods further enrich the current C–Se and C–S bond construction methods.