Summary Bicyclo [3.3. 1 Inon-3-en-9-one-1-carboxylic acid (V) has been prepared by the Michael addition of a-carbethoxycyclohexanone to acrolein at-70", followed by cyclization of the resulting aldehyde I11 by treatment with concentrated sulfuric acid and saponification of the ester IV. Both the acid V and the corresponding saturated acid VI1 resist decarboxylation by heating. Bicyclo-[3.3. 1] nonan-9-one-l-tarboxylic acid (VII) was decarboxylated by ...
