One-pot double annulations to confer diastereoselective spirooxindolepyrrolothiazoles
Juan Lu1, Bin Yao2, Desheng Zhan1
1Department of Chemistry, Changchun Normal University, Changchun 130031, P. R. China.
Abstract:
A novel four-component reaction in one pot as an atom- and step-economic process was developed to synthesize diastereoselectively spirooxindolepyrrolothiazoles through sequential N,S-acetalation of aldehydes with cysteine and decarboxylative [3 + 2] cycloaddition with olefinic oxindoles. High synthetic efficiency, operational simplification and reaction process economy using EtOH as solvent, and only releasing CO2 and H2O as side products confer this approach favorable in green chemistry metrics analysis.
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