Initially, we were focused on the synthesis of pseudocyclic TIPS-ENHIs. Starting from our previous results for the synthesis of cyclic diaryliodonium salts using one-pot procedures, we were intended to directly develop a convenient oxidation/alkynylation reaction. One-pot procedures for unsubstituted TIPS-ethynyl iodonium salts and EBX reagents have already been described, using meta-chloroperbenzoic acid (mCPBA) as the terminal oxidant in the presence of strong acids such as TfOH or TsOH and the subsequent addition of an alkyne to the in situ formed hydroxy(aryl)iodonium salt. Based on these procedures the reaction conditions were optimized for TIPS-ENHIs (Table ). First, the equivalents of TfOH were varied using 2,2,2-trifluoroethanole (TFE) as a solvent. 6 CHCl 3 2.5 (24%) 7 MeCN 2.5 76% 8 MeCN 1.6 (11%) 9 MeCN 2.5 69% 10 MeCN 3.0 71%