Table 1. Au(I)Cl Initiated Cyclization Reactions of Various 2-Alkynylthioimidazoles^abc.

^aIn an MW vial, compound 1 (from 50 mg to 200 mg, 0.17–0.45 mmol) was dissolved in 5 mL of DCE, and AuCl (10 mol %) was added under an argon atmosphere. The sealed vial was subjected to microwave irradiation until full conversion of the starting material.

^bSubstrate 1i (80 mg, 0.30 mmol) was dissolved in 5 mL of DCM, then 10 mol % of AuCl was added, and the reaction mixture was refluxed under an argon atmosphere.

^cDeprotection conditions: to the solution of 2j (140 mg, 0,28 mmol, 1.0 equiv) in DCM (5 mL), TFA (1 mL) was added dropwise. The reaction mixture was stirred at room temperature overnight until full conversion of the starting material.