Synthesis of 2,3,4-trisubstituted pyrrole derivatives via [3 + 2] cyclization of activated methylene isocyanides with 4-(arylidene)-2-substituted oxazol-5(4H)-ones

An efficient base-catalyzed [3 + 2] cyclization between isocyanides and 4-(arylidene)-2-substituted oxazol-5(4H)-ones has been successfully developed to form 2,3,4-trisubstituted and 2,2,3,4-tetrasubstituted pyrrole derivatives.