Damir Z. Absalyamov
Irkutsk State University, Russia
Title: Quantum-chemical investigation of acetylene reactions with aniline in a superbasic KOH/DMSO medium.
Biography
Biography: Damir Z. Absalyamov
Abstract
The relevance of studying the activity of initial amines with acetylenes and the mechanisms of their mutual transformations in a superbasic medium is dictated by the interest in the synthesis of nitrogen-containing heterocyclic compounds with potential biological activity. One example is the synthesis of N-phenyl-2,5-dimethylpyrrole.
Quantum chemical studies were carried out by B2PLYP/6-311+G**//B3LYP/6-31+G* approach. Using the simplest model for describing the superbasic medium, a “virtual screening” of the most probable interactions of acetylene molecules with each other and with the aniline molecule was done. Based on this, the most realistic interaction routes were selected, which were studied in more complex models, taking into account the obvious influence of alkali and solvent.
The experimental results are explained and the mechanism of one-pot N-phenyl-2,5-dimethylpyrrole assembly by sequential addition of three acetylene molecules to an aniline molecule is shown. The possibility of hexa-2,4-diyne formation is low due to the formation of an acetylene polymer such as octa-1,3,5-triene-7-yne, which is more advantageous both kinetically and thermodynamically. The acetylene polymerization reaction is carried out under more stringent conditions, but can compete with the formation of pyrrole.
This work was supported by Ministry of Education and Science of the Russian Federation. Grant Number: FZZEâ€2020â€0025.