Lactamomethylation of phenols: synthesis, in silico study of reactivity, and possible applications

Lactamomethylation of phenols with various substituents was provided by pyrrolidone, valerolactam, caprolactam, and 4-phenylpyrrolidone derivatives. The structures of the target compounds were confirmed by IR and NMR study. The behavior of alkylphenols (2,4-di-tert-butyl- and thymol), diphenols (catechol and hydroquinone), formylphenol (vanillin), and hydroxybenzoic acids (salicylic and resorcylic) in this reaction was compared by quantum-chemical calculations. For several compounds, the energy of dissociation of the ArO-H bond was calculated by quantum-chemical method to reveal their possible antioxidant activity. In addition, the ability of synthesized compounds to destruct cumene hydroperoxide was studied. It was estimated that 1-(4-hydroxy-5-isopropil-2-methylbenzyl)azepan-2-one and 1-(4-hydroxy-5-isopropil-2-methylbenzyl)pyrrolidin-2-one possess the best antioxidant effect, comparable to the one of industrial additive butylated hydroxytoluene (BHT).