S1 Selective Synthesis of N-H and N-Aryl Benzotriazoles by the [3+2] Annulation of Sodium Azide with Arynes Avishek Guin, Rahul N. Gaykar, Subrata Bhattacharjee and Akkattu T. Biju* Department of Organic Chemistry, Indian Institute of Science, Bangalore-560012, India Email: atbiju@iisc.ac.in Supporting Information 1. Optimization Studies for the N-H Benzotriazoles Synthesis S02 2. Optimization Studies for the N-Aryl Benzotriazoles Synthesis S03 3. Mechanistic Experiments S04 4. 1 H and 13 C NMR Spectra of all Products S05