Singlet carbenes can be used to isolate elusive neutral phosphorus radicals in the solid state, researchers have discovered.
Very few phosphorus radicals have been isolated and characterised in the solid state because they tend to dimerise. Now, Guy Bertrand and colleagues have reported two phosphorus radicals, one stabilised by a transition metal and the other stabilised by N-heterocyclic carbenes (NHCs), which allowed them to compare the electronic effects of both substituents. While the transition metal was better at delocalising the spin density from the phosphorus nucleus, NHCs are sufficiently stabilising to allow isolation and characterisation of the neutral radical.
Download Bertrand’s Edge article from Chemical Science to read more.
