One-Pot Synthesis of 1-[(Triisopropylsilyl)ethynyl]-1,2-benziodoxol-3(1H)-one (TIPS-EBX): Process Safety Assessment and Impact of Impurities on Product Stability

The hypervalent iodine reagent 1-[(TriIsoPropylSilyl)Ethynyl]-1,2-BenziodoXol-3(1H)-one (TIPS-EBX) is among the most useful electrophilic and somophilic alkynylation reagents. Herein, we report a new synthetic protocol to access this reagent in one step from standard commercially available reagents. Thermal analysis of the synthesis procedure showed only weak exotherms. The compound could be obtained with high purity and stability using this new protocol, but care had to be taken to remove tosylate salts impurities, as they led to a lower thermal stability. TIPS-EBX synthesized using the new procedure displayed no shock sensitivity.