Synthesis of functionalized 2-pyrrolidinones via domino reactions of arylamines, ethyl glyoxylate and acetylenedicarboxylates

An efficient and practical synthetic method for the functionalized 2-pyrrolidinones was successfully developed via the domino reactions of ethyl glyoxylate and acetylenedicarboxylate with 2 M arylamines in the presence of benzoic acid as catalyst. When two kinds of amines were used in the reaction, the stronger nucleophilic aliphatic amine preferentially added to acetylenedicarboxylate to form the reactive intermediate β-enamino ester and the reaction showed high regioselectivity.