Glycerol‐1,2‐carbonate: A mild reagent for the N‐glycerylation of pyrazolecarboxylates

Abstract

AbstractIn this study, glycerol‐1,2‐carbonate was employed as a convenient reagent for the synthesis of more complex pyrazole‐containing heterocyclic systems. 3‐O‐Tosylated glycerol‐1,2‐carbonate (TGC) was used for alkylation of NH‐pyrazolecarboxylates. The obtained N‐glycerylated pyrazoles were further treated with diverse nucleophiles for 2‐oxo‐1,3‐dioxolane ring cleavage. The synthesized 1‐(2,3‐dihydroxypropyl)‐1H‐pyrazole‐5‐carboxylates were subsequently hydrolyzed and treated with p‐toluenesulfonic acid, yielding a series of 6‐(hydroxymethyl)‐6,7‐dihydro‐4H‐pyrazolo[5,1‐c][1,4]ox‐azin‐4‐ones.