文摘
A general approach to 2-substituted ethyl 5-aminothiazole-4-carboxylates is reported herein. Both aliphatic and aromatic thioamides undergo 1,2-addition to ethyl glyoxylate to give hemiaminals which, when treated with acetyl chloride, undergo elimination to the corresponding imines. Upon exposure to aqueous sodium cyanide the imines undergo a Strecker addition–cyclization reaction to provide the target heterocycles in modest to good yields over the 3-step process.