Polyalkylated azulenes can easily be prepared from polyalkylphenyl propiolates which are transformed by dynamic gas phase thermo-isomerization (DGPTI) into polyalkylcyclohepta[b]furan-2(2H)-ones. The latter react thermally with enol ethers or enamines to the corresponding azulenes. The enamines may be generated in situ from corresponding aminals, especially, in cases where it is difficult to obtain the pure enamines due to their high reactivity.