Mahnaz Saraei, Maaroof Zarei and Saleheh Zavar Pages 597 - 602 ( 6 )
Background: 2-Azetidinones (β-lactams) has occupied an important role in organic chemistry and drugs. β-Lactam antibiotics are extensively applied to fight against microorganisms as antibiotic drugs. The Staudinger's ketene-imine cycloaddition is one of the most common approaches in the synthesis of 2-azetidinones. The aim of this paper to describe a methodology based on the use of 3- (diethoxyphosphoryloxy)-1,2,3-benzotriazin-4-(3H)-one (DEPBT) for the synthesis of 2-azetidinones under mild reaction conditions at room temperature.Methods: The present methodology deals with one pot [2+2] ketene-imine cycloaddition reaction of imine and substituted ketene to synthesis of 2-azetidinones in mild condition at room temperature. In addition, detailed experimental procedures are provided. Results: A series of 2-azetidinones were synthesized in good to excellent yield via one pot [2+2] ketene-imine cycloaddition reactions. The obtained products were purified in good yield by simple crystallization. All the synthesized compounds were well characterized by spectral and physical data. Conclusion: A simple method for one-pot transformation of various carboxylic acids and imines to 2- azetidinones using 3-(diethoxyphosphoryloxy)-1,2,3-benzotriazin-4-(3H)-one (DEPBT) has been developed. The yield of [2+2] ketene-imine cycloaddition was good to excellent, and starting materials were readily available. An aqueous work up and simple crystallisation was sufficient to obtain pure products because DEPBT produces water-soluble by-products.
β-Lactam, 2-Azetidinone, Staudinger reaction, DEPBT, Ketene, Imine.
Department of Chemistry, Payame Noor University, P.O. Box. 19395-3697, Tehran, Department of Chemistry, Faculty of Sciences, University of Hormozgan, Bandar Abbas 71961, Department of Chemistry, Payame Noor University, P.O. Box. 19395-3697, Tehran