Arylation of diazoesters by a transient N-H insertion organocascade.

It takes two: A unique organocatalyzed cascade for the unsymmetric double arylation of α-nitrodiazoesters is described. This organocascade features the strategic use of carbene-activating anilines in conjunction with a urea catalyst, thus allowing for the synthesis of pharmaceutically attractive α-diarylesters through a transient NH insertion process.