Observations on the samarium diiodide-promoted C-C fragmentation/ring expansion chemistry of some aliphatic 1,4-diketones

The observations on the samarium diiodide-promoted C-C fragmentation/ring expansion chemistry of some aliphatic 1,4-diketones were presented. It was found that some photochemical electron transfer, as well as SmI₂-mediated transformations were carried out on non-aromatic substrates. It was shown that given the otherwise identical molecule, the ability of the SmI₂ HMPA complex to chelate the 1,4-dicarbonyl moiety in the one case and not in the other is the primary factor that determines the fragmentation reaction.