Lactamomethylation of alkylphenols: Synthesis and quantum-chemical study of the reaction pathway

Six novel lactamomethyl derivatives of 2,5-dimethylphenol and 2,3,5-trimethylphenol were prepared with moderate yields by the reaction of corresponding phenols with 1-(hydroxymethyl)lactams in the presence of an acid catalyst. In all cases, the substitution occurred at position 4 to the phenolic hydroxyl group. The structures of all synthesized compounds were confirmed by FT-IR, ¹H and ¹³C NMR, 2D NMR and elemental analysis. The selectivity and possible pathways of the lactamomethylation reaction were studied by quantum-chemical methods. In silico calculations showed that the substitution at para-position to the hydroxyl group of the corresponding phenols was more preferable due to the higher stability of forming intermediates.