Enamine chemistry. Part 26. Preparation of substituted adamantane-2,4-diones and bicyclo[2.2.2]octan-2-ones
Abstract
Reaction of αβ-unsaturated acid chlorides with the morpholine or pyrrolidine enamines derived from 4-benzoyl-4-methylcyclohexanone gives the corresponding 6-hydroxy-7-methyl-6-phenyladamantane-2, 4-dione in moderate to good yield. Enamines from 4-acetyl-4-phenyl (or 4-ethoxycarbonyl) cyclohexanone could not be isolated owing to their preferential cyclisation into 1 -phenyl (or 1 -ethoxycarbonyl) 4-substituted aminobicyclo[2.2.2]octan-2-ones.