Three‐Component Domino Knoevenagel/Hetero‐Diels–Alder Reaction for the Synthesis of the Amino Sugars 2‐Acetoxyforosamine and 2‐Acetoxyossamine – Experimental and Theoretical Results

Abstract The three‐component domino Knoevenagel/hetero‐Diels–Alder reaction of nitroacetone ( 6 ), formaldehyde and ethoxyvinylacetate ( 4 ) leads to dihydropyrans 10 and 11 , which after hydrogenation of the double bond as well as consecutive reduction of the nitro group and reductive amination give the desired forosamine‐type 2‐acetoxyamino sugars 21 – 24 and ossamine‐type 25 .