A Se···O bonding catalysis approach to the synthesis of calix[4]pyrroles
Qingzhe Tong1, Zhiguo Zhao1, Yao Wang1
1School of Chemistry and Chemical Engineering, Key Laboratory of the Colloid and Interface Chemistry, Shandong University, Jinan 250100, China.
Abstract:
Described herein is a chalcogen bonding catalysis approach to the synthesis of calix[4]pyrrole derivatives. The Se···O bonding interactions between selenide catalysts and ketones gave rise to the catalytic activity in the condensation reactions between pyrrole and ketones, leading to the generation of calix[4]pyrrole derivatives in moderate to high yields. This chalcogen bonding catalysis approach was efficient since only 5 mol % catalyst loading was used to promote the consecutive condensation processes while the reactions could be carried out at room temperature, thus highlighting the potential of this type of nonclassical interactions in catalyzing relative complex transformations.
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