Reactions between enaminones and enones. Part 2. C versus N-Alkylation with cyclohex-2-enone. Structure confirmation by reduction of a dienaminone derivative of dehydrated dimedone dimer

Abstract

Primary and secondary enaminones derived from cyclohexane-1,3-dione, dimedone, and acetylacetone react with cyclohexenone to give exclusively C-alkylated derivatives. In every case the products form carbinolamines which exist as 1-hydroxy-2-azacyclo[3.3.1]nonenes. This was confirmed in some examples by formation of an extra ring between nitrogen and oxygen. A series of dienaminones were prepared from 2-(5,5-dimethyl-3-oxocyclohex-1-enyl)-5,5-dimethylcyclohexane-1,3-dione and one of these was reduced to give an azanonene identical with that from C-alkylation.