Tautomerism of bis(2,4-benzyloxy)-6-(5H)-one-1,3,5-triazine: A combined crystallographic and quantum-chemical investigation

In order to study the keto and enol forms of cyanuric acid derivatives in the solid state, we have synthesized bis(2,4-benzyloxy)-6-(5H)-one-1,3,5- triazine, 1. Computational investigations indicate that keto form is more stable than enol form in both gas phase and solution phase by 9.69-11.18 kcal mol ^-1 IR and crystallographic analysis shows that 1 exists in keto form in the solid state also. To obtain the enol form in the solid state, we adopted co-crystallization with an organic base. The crystal structures of both keto/amine and the enol/imine forms (in a co-crystal) are reported.