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Preparation of Stable Bicyclic Aziridinium Ions and Their Ring-Opening for the Synthesis of Azaheterocycles
Published on: August 22, 2018
Determination of dibenzo[b,f]-1,4-oxazepine by diazotization cleavage of azomethine bond
E Hálamek1, Z Kobliha, V Földesi
1Department of Chemistry, Faculty of Arms, Military University, 682 03 Vyskov, Czech Republic.
Abstract:
A spectrophotometric determination of dibenzo[b,f]-1,4-oxazepine (CR) has been elaborated, which is based on a diazotation cleavage of azomethine bond followed by a coupling reaction. Twelve coupling agents have been used in the experiments and the following three agents have been recommended for the determination: N-(1-naphthyl)ethylenediamine dihydrochloride (L(Q) = 85 mg/ml), 7-hydroxy-4-methyl coumarin (L(Q) = 105 mg/ml) and 1-naphthol (L(Q) = 110 mg/ml). 2-[2-(hydroxy-l-naphthylazo) phenoxy]benzaldehyde has been identified by (1)H and (13)C NMR and elementary analysis as the product which results from the diazotization reaction followed by coupling of the CR substance with 2-naphthol. The azo-dye prepared by the described reactions shows azo-hydrazo tautomerism.
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