Simple Synthesis of Bicyclic Pyrrole Ketone Compounds

In this article, a one-pot protocol was established for the synthesis of bicyclic pyrrole ketone compounds. This method based on the building blocks of heterocyclic ketene aminals 1, which reacted with oxalaldehyde 2 in 1,4-dioxane at 50 degrees C and triethylamine as base. As a result, a series of bicyclic pyrrole ketone compounds 3a similar to 31 have been synthesized. This reaction has some advantages such as simple synthetic route, readily available starting materials, high yields and simple work-up procedures.