2-Oxocyclohexane carboxylic derivatives

Various 1,5-disubstituted derivatives of bicyclo[3,3 l]nonane have been prepared from (662), the desulphurization by Raney-Nickel being the first step. Reactions of pyrrolidine enamines of dialkyl 4-oxocyclohexane-l,l dicarboxylates (663) with acryloyl chloride give alkyl 2,6-dioxobicyclo[3,3,l]nonane-l-carboxylates (666) rather than the expected alkyl 2,9-dioxobicyclo[3,3,l]nonane-7-carboxylate. However, the enamines (664) and (665) give rise to the normal products, and reasons for the change in reaction course are advanced. 

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