Cited research: Science 328, 1376–1379 (2010)

Iodine has the potential to replace the toxic and rare metals used as catalysts in many reactions.

Certain reactions yield a mixture of two mirror-image, or 'chiral', products. To produce only one or other of these, iodine catalysts have generally been fitted out with a chiral aromatic ring. Now, Kazuaki Ishihara and his colleagues at Nagoya University in Japan demonstrate an extremely selective catalysis using iodine that is instead converted in situ to either IO− or IO2−.

The resulting catalyst induced selectivity between chiral forms, successfully converting ketophenols to 2-acyl-2,3-dihydrobenzofurans with extremely high selectivity for one form. This shows the potential for iodine catalysts without aromatic rings to replace traditional transition-metal catalysts. D.C.