Small ring insertion expands structural editing toolbox


Bicyclic ring system made by adding a bicyclobutane into a thiophene

A photoredox-induced radical pathway is behind a synthetic strategy that allows users to insert a small ring into a heterocyclic parent ring. Frank Glorius from the University of Münster in Germany, who developed the method with Kendall Houk at the University of California, Los Angeles in the US, compared it to sleight-of-hand magic. ‘Maybe a magician throws two solid rings in the air or hides them under a cloth, but the next time the audience see them they’re connected. This is exactly what’s happening in our work, only it’s not a cheap trick, it’s catalytic activation.’