Introducing Amino Derivatives at the 3‐Position of Benzothiophene S , S ‐Dioxide

The addition of aliphatic amines to 3,5,6‐tribromobenzothiophene S , S ‐dioxide ( 3,5,6‐Br‐BTO ) readily leads to substitution of the bromine atom at the 3‐position via a nucleophilic addition–elimination pathway. Among aromatic amines, only the most nucleophilic derivatives undergo successful incorporation under these conditions. To broaden the scope to a wider range of amines, 3,5,6‐Br‐BTO was converted into 5,6‐dibromobenzothiophenone S , S ‐dioxide ( 5,6‐Br‐BTKO ). This activated intermediate enables efficient condensation under microwave irradiation, affording the corresponding amino derivatives without the need for chromatographic purification.