Vapor phase synthesis of alkylpyrazines over ZnAl mixed oxide derived from layered double hydroxides obtained by the mechanochemical method

This study emphasizes on using different types of reactants to obtain compounds belonging to the same class, alkylpyrazines. The mechanism of these reactions is one of cyclo-dehydrogenation on the surface of a mixed oxide catalyst, e.g. ZnAl. Different types of reactions have been performed, using diamines, hydroxyamines or a diamine and a diol. The raw materials used and the various reaction parameters like temperature, space velocity and molar ratio of the reactants present a significant influence in the conversion and selectivity values. The conversion of reactants was quasi-total while the selectivity of the yielded products varies from 95.9% to a complex mixture of products. The ZnAl catalyst is thermally stable with the catalytic sites easily regenerated. Graphical abstract: [Figure not available: see fulltext.].