Tetrazol-5-one, 1-aryl

Tefrazolo[2,3-e]isoxazole, 2-methyl-IR spectra, 6, 978 Tetrazol-5-one, 1-aryl-acylation, 5, 821 Tetrazol-5-one, 1,4-dimethyl-2-oxides synthesis, 3, 533... 

The intramolecularity of the thermal rearrangement of 1 -aryl-5-allyloxy-1H-tetrazoles to l-aryl-4-allyl-l,4-dihydrotetrazol-5-ones has been investigated through... 

A one-pot protocol for the synthesis of 1-aryl-5-(N-aryl-N-aroylamino)-tetrazoles 247 from symmetrical diaryl carbodiimides 243 with sodium azide under phase transfer conditions in toluene at room temperature was developed by Ding and Weber. The carbodiimide 243 reacts with sodium azide to form a guanyl azide 244 which, after reaction with an aroyl chloride 245, imdergoes electrocycHzation to yield the substituted tetrazole 247 (Scheme 47). The reaction is limited to symmetrical diaryl carbodiimides. Di-aUcyl carbodiimides fail to react imder these conditions while asymmetrical diaryl carbodiimides lead to a mixture of tetrazole isomers [157]. 

The reaction of sodium azide with N-aryl chloroimines, obtained from benzanilides and thionyl chloride, to form 1,5-disubstituted tetrazoles is catalysed by tetra-n-butyl-ammonium bromide (Scheme 5.26, Table 5.40) [18] in variable yields, but generally <85%. 5-Butyl-2,3-diphenyltetrazolium salts have also been used as catalysts [18, 19]. 1,5-Disubstituted tetrazoles are also obtained from a one-pot sequential reaction of carbodimides with sodium azide and an aroyl chloride in the presence of tetra-n-butylammonium chloride [20]. 5-Chlorotetrazoles are obtained from the catalysed reaction of aryldichloroisocyanides with sodium azide (Scheme 5.26) [21],... 

Other 1,2-diazines synthesized included 4-amino-3-cinnolinecarboxylic acids <97PHA91 >, I -aryl-6-chloro-l,4-dihydro-4-oxothieno[2,3-c]pyridazine-3-carboxylic acids <97JPR284>, 2H-benzo[2,3-g]pyridazino[4,5-<7,e]quinolin-3-ones <97M681>, 3-chloro-4-carbamoyl-5-aryl-6-methylpyridazine N-oxides <97F67>, 2-aroyl-6-(hetero substituted)-3(2//)-pyridazinones <97HCM267>, and 5-(4-hydroxycinnolin-3-yl)tetrazoles 2-methyl-5-(4-acetoxycinnolin-3-yl)-... 

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