Formation of a spiran structure in the condensation of 2-azafluorene with esters of α, ß-unsaturated acids

4′-Hydroxy-3-methyl-2′,6′-diphenyl-3′ethoxycarbonylspiro(2-azafluorene-9, 1′-cyclohex-3′-ene) was obtained by condensation of 3-methyl-2-azafluorene with ethyl cinnamate in the presence of potassium. The chemical mechanism of its formation and its three-dimensional structure are discussed. © 1977 Plenum Publishing Corporation.