diazotization of 3-amino-2-cmoro pyridine (3) in the presence of dithizone (5) gave dphenyl-2-phenylazo-4h-pyrid[o3 ,2-e] [1,3,4] thiadiazine (6). reaction of 2- chloro-3-nitropyridine (2, g=h) with (5) dfordd 4-phenyl -2-phenylazo -4hpyrido [2,3-el [1,3,4] thiadiazine (7). reduction of the latter with h gas in the presence of raney nickel gave the corresponding amino derivative (12). one pot c...

The composite diazotization coupling reaction of sulfanilic acid and N, Ndimethylaniline was used for the precise, accurate, and rapid determination of trace amounts of nitrite ion (0.02-3 µg/ml). The reaction was monitored spectrophotometrically by measuring the absorbance of the produced methyl orange at 510 nm by a fixed the method of 5.0 minutes. The relative standard deviation for the...

Treatment of 7-chloro-1-phenylpyrimido[4,5-e][1,3,4]thiadiazines with hydrazine in boiling ethanol gave corresponding7-hydrazinyl derivatives. Diazotization of the latter compounds acheived a mixture of 5H-tetrazolo[1',5':1,2]pyrimido[4,5-e][1,3,4]thiadiazine and 9H-tetrazolo[5',1':2,3]pyrimido[4,5-e][1,3,4]thiadiazines. Ratio of these two group of products d...

3,3'-Dicarboxy-4,4'-diaminobiphenyl was synthesized from Onitrobenzoic acid following standard procedures. Diazotization of this compound with isoamylnitrite, under approtic condition gave diphenyl-4,4'-bis-diazonium-3,3'-dicarboxylate and subsequent thermal decomposition of this diazonium compound produced 3,4,3',4'-tetradehydrobiphenyl (bisbenzyne) as a reactive intermediate. Bisbenzyne w...

A convenient, one-pot method for the synthesis of diazonium salt has been developed by the sequential diazotization of aromatic amines with NaNO2, polymer- supported periodic acid (PPIA) and 2-naphthole under solvent-free conditions at room temperature. By using this method, several types of aromatic amine, containing electron-withdrawing and electron-donating groups, were rapidly converted to ...

Treatment of 7-chloro-1-phenylpyrimido[4,5-e][1,3,4]thiadiazines with hydrazine in boiling ethanol gave corresponding7-hydrazinyl derivatives. Diazotization of the latter compounds acheived a mixture of 5H-tetrazolo[1',5':1,2]pyrimido[4,5-e][1,3,4]thiadiazine and 9H-tetrazolo[5',1':2,3]pyrimido[4,5-e][1,3,4]thiadiazines. Ratio of these two group of products d...

A series of five tetracyclic mono azo dyes based on the diazotization 1-amino-8-hydroxynaphthalene-3,6-disulphonic acid and subsequent coupling with substituted (un)sulphonated naphthalene derivatives have been synthesized. The chemical structures were established using UV–visible, IR, NMR as well mass spectrometry. Based number sulphonic other hydrophilic groups they contain, compounds showed ...