Unlocking the N² Selectivity of Benzotriazoles: Regiodivergent and Highly Selective Coupling of Benzotriazoles with Allenes

The rhodium-catalyzed, highly N(2) - and N(1) -selective coupling of benzotriazoles with allenes is reported. The exceptionally high N(2) and N(1) selectivities were achieved by using a rhodium(I)/DPEphos and rhodium(I)/JoSPOphos catalyst, respectively. This method permits the atom-economic synthesis of valuable branched N(2) - and N(1) -allylated benzotriazole derivatives and allows for preliminary studies of their reactivity.