Preparation of ²¹¹At-Labeled (Hetero)aryl Compounds from Triarylsulfonium and Dibenzothiophenium Salts

²¹¹At-labeled (hetero)aryl compounds were obtained from arylsulfonium salt in high RCY with a short reaction time. Benzothiophenium salts appear to be superior to triarylsulfonium salts with a high efficiency demonstrated on electronically enriched or depleted phenyl rings and an <i>ortho</i>-substituted substrate. As a potential application, a ²¹¹At-labeled benzylazide prosthetic group was produced and conjugated to octreotate by SPAAC. This procedure offers an alternative to previous approaches that generally require toxic or unstable precursors and/or catalysts, and/or lead to inseparable products.