Adamantane Derivatives IV: Unexpected Debenzylation on Ring Closure of 1-(1-Adamantylcarbonyl)-4-benzylthiosemicarbazide with Sulphuric Acid

Article abstract of DOI:10.1007/BF00811852

Cyclization of 1-(1-adamantylcarbonyl)-4-substituted thiosemicarbazides 2a-e with sulphuric acid at ambient temperature or by heating with phosphorus oxychloride yielded the corresponding 2-(1-adamantyl)-5-amino-1,3,4-thiadiazoles 3a-e.Cyclization of 1-(1-adamantylcarbonyl)-4-benzylthiosemicarbazide 2f with sulphuric acid gave the debenzylated product 2-(1-adamantyl)-5-amino-1,3,4-thiadiazole 4.On the other hand, cyclization of 2f using phosphorus oxychloride yielded 2-(1-adamantyl)-5-benzylamino-1,3,4-thiadiazole 3f. - Keywords: Adamantanes; Debenzylation; 1,3,4-Thiadiazoles.