Towards the search for new electrophiles: urea formamidines

Abstract

Formamidines and ureas are of great interest as components of biologically active molecules, synthetic reagents and components of functional materials. The development of new compounds containing these functions is therefore of practical interest. In this sense, isonitriles and ureas have been found to undergo a condensation reaction in the presence of acid chlorides to give formamidine ureas, for which no other general synthetic routes currently exist. These compounds have emerged as powerful tunable electrophiles displaying a rich manifold of reactivity, which is governed primarily by the electron-donating power of the imine nitrogen substituents.