Room-Temperature Nucleophilic Aromatic Substitution of 2‑Halopyridinium Ketene Hemiaminals with Sulfur Nucleophiles

2-Thiopyridines and their derivatives are a valuable class of bioactive compounds for drug discovery. However, many synthetic approaches toward these compounds rely on metal catalysis, high-boiling solvents, and/or elevated reaction temperatures. Herein we report a simple mix-and-stir protocol for the synthesis of novel 2-thiopyridiniums, leveraging the recently developed reagent 2-chloro-1-(1-ethoxyvinyl)-pyridinium triflate and readily accessible thiol or thiolate nucleophiles.