Yan-Song Zheng

Nanosized MCM‐41‐SO₃H based on ordered mesoporous silica material with a covalent sulfonic acid group was synthesized and used as acid catalyst for the new, simple, convenient and green synthesis of 2,4,5‐trisubstituted and 1,2,4,5‐tetra‐substituted imidazoles. Also some of synthesis products are new. Echo‐friendly protocol, short reaction times, easy and quick isolation of the products and excellent yields are the main advantages of this procedure.

A simple and eco‐friendly method for the preparation of 1,5‐diaryl‐3‐(arylamino)‐1H‐pyrrol‐2(5H)‐ones via the cyclo‐condensation reaction of aldehydes, amines and ethyl pyruvate in the presence of silica supported ferric chloride (SiO₂‐FeCl₃) as reusable heterogeneous catalyst is described. The present methodology offers several advantages such as excellent yields, simple procedure and short reaction times.

Polyalkylenedioxypyrrole (PADOP) exhibited an excellent conductivity experimentally. A series of oligomers for the electron‐rich monomer alkylenedioxypyrrole (ADOP) were designed in order to study properties of PADOP. The structures of these oligomers were optimized using density function theory (DFT) at B3LYP/6‐31G(d) level. The energy gaps and thermal stabilities of the oligomers were decreased when the chain lengths were increased. These properties were also decreased with the enlargement of the neighboring substituted rings. The ¹³C nuclear magnetic resonance (NMR) spectra and nucleus independent chemical shifts (NICS) of the oligomers were calculated at B3LYP/6‐31G(d) level. The chemical shifts at δ 96.1 of the linking carbon atoms in the dimer of 3,4‐methylenedioxypyrrole (MDOP) were moved downfield relative to those at δ 89.5 of the same carbon atoms in the monomer of MDOP. The aromaticity of the central pyrrole ring in the oligomers is improved with the enlargement of the neighboring substituted rings.