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

Boston College Department of Chemistry Chestnut Hill MA 02467 USA Chestnut Hill MA 02467 USA
Structural Chemistry (Impact Factor: 1.84). 12/2006; 17(6):561-568. DOI: 10.1007/s11224-006-9058-5


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.

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