ORGN 9

My research in this area will be prefaced by a review of the origins of organohypervalent  iodine chemistry. My interest was focussed in 1982 on a search for a reagent that could transfer an oxygen atom to a substrate in a manner similar to an oxygenase system and perhaps also undergo a redox cycle. We envisioned PhIO as such a potential oxene donor (Eqn 1).

(Eqn 1)

In a search for a solvent for PhIO, we chose methanol and this led to our first new reaction, namely, α-hydroxydimethyl acetal formation (Eqn 2):

 (Eqn 2)

This opened our eyes to a fundamental concept in organohypervalent iodine, namely, the sequential assembly of ligands around the iodine center as a key mechanistic step(Eqn 3).

(Eqn 3)

Thus, oxidative addition, ligand exchange and reductive ligand coupling constitute a basic theme of organohypervalent iodine. α /β-Functionalization of carbonyl compounds, carbon-carbon bond formation, oxidative displacement at bridgehead system, Hofmann rearrangement and intramolecular cyclopropanation will be presented.