Oxa-michael addition reactions of 3-hydroxy-2-azetidinones: synthesis of 1,3,4-trisubstituted-2-azetidinones

: The manuscript describes a facile and efficient methodology for the synthesis of 1,3,4- trisubstituted-β-lactams by base mediated oxa-Michael addition reactions of 3-hydroxy-2-azetidinones with acetylenic esters under different reaction conditions. These functionalized 1,3,4-trisubstituted-azetidin-2-ones are useful organic synthons for the synthesis of various heterocyclic compounds having diverse pharmacological applications.

Synthesis of functionalized benzo[1,3]dioxin-4-ones from salicylic acid and acetylenic esters and their direct amidation

An efficient method for the synthesis of the active core 4H-benzo[d][1,3]dioxin-4-one followed by its direct room temperature amidation is reported.