Configurations and conformations of some 3-acetoxy-cis-hexahydro-2(3H)-benzofuranones

Catalytic hydrogenation of some 2-ethoxalylcyclohexanones afforded a mixture of isomeric 3-hydroxy-cis-hexahydro-2(3H)-benzofuranones. Three 5-t-butyl substituted diastereomers and two 5-unsubstituted epimers were separated and identified as acetates. The configurations were determined by 350 MHz ¹H-nmr analysis. The conformations of these fused-compounds are discussed.