Tautomerism of triazoles

More recently, activity in the held of the preparation of phthalocyanine-like compounds useful in material science concentrated on compounds containing only one triazole subunit (triazolophthalocyanines) 89 [94JCS(CC)1525 95ICA(230)153].These aromatic compounds (without or with metals in the cavity) present a problem of annular tautomerism of triazoles, but as yet it is known only that the NH is outside the cavity. 

Dabbagh HA, Rasti E, Chermahini AN (2010) Theoretical studies on tautomerism of triazole derivatives in the gas phase and solution. J Mol Struct (Theochem) 947 92-100... 

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