A novel method for the stereospecificsynthesis of 1,5-disubstituted tetrazoles from ketoximes via the Beckmann rearrangement was developed using diphenyl phosphorazidate (DPPA) as both the oxime activator and azide source. Various ketoximes were transformed into the corresponding 1,5-disubstituted tetrazoles with exclusive trans-group migration and no E-Z isomerization of the ketoxime. This method
On treatment with an excess of sodium azide in the presence of titanium(IV) chloride in boiling acetonitrile, both aliphatic and aromatic ketones are smoothly converted to 1,5-disubstituted 1H-tetrazoles in high yields.
A novel method has been developed for the synthesis of 1,5-disubstituted tetrazoles from nitrones by using bis(p-nitrophenyl) phosphorazidate in the presence of 4-(dimethylamino)pyridine. By this approach, various nitrones were converted into the corresponding tetrazoles. This method permits the preparation of 1,5-disubstituted tetrazoles without the need for toxic or explosive reagents.
Facile Preparation of 5-Alkyl-1-aryltetrazoles with Arenes, Acyl Chlorides, Hydroxylamine, and Diphenylphosphoryl Azide
作者:Hideo Togo、Kaho Shibasaki
DOI:10.3987/com-20-14321
日期:——
<i>o</i>-Iodoxybenzoic Acid Mediated Oxidative Desulfurization Initiated Domino Reactions for Synthesis of Azoles
作者:Pramod S. Chaudhari、Sagar P. Pathare、Krishnacharaya G. Akamanchi
DOI:10.1021/jo2025509
日期:2012.4.20
A systematic exploration of thiophilic ability of o-iodoxybenzoic acid (IBX) for oxidative desulfurization to trigger domino reactions leading to new methodologies for synthesis of different azoles is described. A variety of highly substituted oxadiazoles, thiadiazoles, triazoles, and tetrazoles have been successfully synthesized in good to excellent yields, starting from readily accessible thiosemicarbazides, bis-diarylthiourea, 1,3-disubtituted thiourea, and thioamides.