Bridged ring systems. Part XVII. The mechanism of a transannular acylation
Abstract
Earlier reports that diethyl 5-methylcyclo-oct-4-ene-1,1 -dicarboxylate was transformed into 5-methyl-9-oxobicyclo[3,3,1]non-3-ene-1-carboxylic acid by aqueous alkali and into 1 -hydroxymethyl-5-methylbicyclo [3,3,1]non-3-en-9-ol by reduction with lithium aluminium hydride are shown to be erroneous. These products arise from a bicyclic impurity formed by an acid-catalysed process.