A Click Chemistry Approach to Tetrazoles by Huisgen 1,3-Dipolar Cycloaddition: Synthesis of 5-Sulfonyl Tetrazoles from Azides and Sulfonyl Cyanides We thank the National Institute of General Medical Sciences, National Institutes of Health (GM-28384), the National Science Foundation (CHE-9985553), the Skaggs Institute for Chemical Biology for a Predoctoral Fellowship (Z.D.), and the W. M. Keck Foundation for financial support. Dedicated to Professor Rolf Huisgen, the pioneer of this large and extremely useful family of reactions.