Synthesis and Reactivity of 3-Aminothiophenes and 3,4-Diaminothiophenes

Ten years ago, thiophenamines and thiophenediamines, usually called aminothiophenes and diaminothiophenes, were the subject of an important report.[1] 3,4-Diaminothiophenes have also received separate attention.[2] For a long time, N-(2-thienyl)acetamide and alkyl 2-thienyl carbamates have been extensively studied, 2-aminothiophene itself being considered as very unstable. However, 2-aminothiophenes with electron-withdrawing substituents or functional groups are the subject of numerous papers.[1]