An Easy and Convenient Synthesis of β-Lactams via a One-Pot Staudinger Reaction with 4-(4,6-Dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium Chloride Starting from Substituted Carboxylic Acids

An easy and convenient direct synthesis of 2-azetidinones is described. The [2+2] cycloaddition reaction of imines and carboxylic acids using 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride (DMTMM) has been employed to synthesize a variety of 2-azetidinones in high yields. The products were easily isolated because the byproducts are highly soluble in water.