Trisubstituted Cyclohexanes / Trisubstituted Cyclohexanes

C-Tertiarv vinylketones or the corresponding masked vinylketone derivatives react with pyrrolidin-2-one in the system sodium hydride.dimethylsulfoxide to substituted cyclohexanes of the 1,3.5- and sometimes additionally of the 1,2.4-type. Only acetophenone Mannich bases bear­ing a p-hydroxy or a dimethylamino group failed in cyclization.