methodology for the synthesis of aryl/alkyl cyanamides from amines in one-pot four steps reaction using cheap, readily available and air stable copper source as catalyst under mild reaction conditions. We have also studied the application of cyanamides. In this connection, we could construct aryl tetrazolamine from cyanamides using click reaction GRAPHICAL ABSTRACT
A one pot, three component synthesis of tetrazoles via thiourea has been accomplished in water. Water enhances the solubility of a higher number of components in the three component protocol thus promoting the reaction. The synthesis involves a chemoselective exocyclic reaction, regioselective electrocyclisation and a preferred conformational orientation of the tetrazole side chain which are rationalised based on the relative magnitude of Garbisch angle strain/allylic strains anticipated during the course of the reaction.
<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.
Synthesis of 3(s)-acylamino-1-[(phenyl)(1h-tetrazol-5-yl)amino]-2-azetidinones