Site-selective Aryne Formation from Aryl Sulfonium Salts En-abled by Intramolecular Functional Group Translocation.

Recent advantages in the field of aryl sulfonium salts made these salts readily avaible in one chemical step from common functional groups. A new class of aryl sulfonium salts was developed to improve the site-selectivity of the aryne formation via deprotonation/elimination sequence. Mechanism study revealed an intramolecular aryne translaoction pathway enabled by the reversible proton transfer. Current method could enable late stage (hetero)aryne formation on the pharmaceuticals and greatly reduce the synthetic effort to access structurally highly diversed (hetero)aryne. Mild condition and broad scope pro-vide orthogonal reactivity compared with Kobayashi aryne precursors.