Thermolysis of 3-isopropyl- and 3-cyclobutyl-3- ferrocenylcyclopropenes res
ults in the formation of 3-alkylidene-3- ferrocenylpropynes and (Z ,E)-1-al
kyl-1-ferrocenylpropenes; 2,2-dibromo-1-methyl-, 2,2-dibromo-1-isopropyl- a
nd 2,2-dibromo-1-cyclobutylferrocenylcyclopropanes are converted into ferro
cenylvinylacetylenes on treatment with (BuOK)-O-t in THF.