Identifying Amidyl Radicals for Intermolecular C-H Functionalizations.

Recent studies have demonstrated the capabilities of amidyl radicals to facilitate a range of intermolecular functionalizations of unactivated, aliphatic C-H bonds. Relatively little information is known regarding the important structural and electronic features of amidyl and related radicals that impart efficient reactivity. Herein, we evaluate a diverse range of nitrogen-centered radicals in unactivated, aliphatic C-H chlorinations. These studies establish the salient features of nitrogen-centered radicals critical to these reactions in order to expedite the future development of new site-selective, intermolecular C-H functionalizations.

Visible-light-mediated, nitrogen-centered radical amination of tertiary alkyl halides under metal-free conditions to form α-tertiary amines.

A mild and operationally convenient amino-functionalization of a range of tertiary alkyl halides by reaction with iminoiodinanes (PhI[double bond, length as m-dash]NNs) and I2 has been developed. According to the mechanistic experiments described within, the reaction is speculated to proceed through a light-promoted, N-centered radical pathway involving a N,N-diiodosulfonamide reactive species. This method of direct N-incorporation offers an attractive alternative to the production of α-tertiary amines, a synthetically challenging structural class found in a variety of bioactive molecules.