A convenient and versatile procedure for the straightforward synthesis of substituted fluorenones as valuable scaffolds is described under rhodium catalysis. The present [2 + 2 + 2] cycloadditionreaction of diynes with 3-acetoxy or-3-alkoxyindenones as surrogates of the highly reactive benzocyclopentynone 2π partner allows the preparation of various fluorenone-type derivatives in good yields and provides
Further investigations on our recently discovered goldcatalysed cyclisation reaction of 1,6-diynes are reported. By varying the steric and electronic nature of the alkyne substituents, the potentials and limitations of the new reaction have been identified.