para-Selective C–H Functionalization through Radical Substitution
The chelation-assisted approach for C–H functionalization is very successful and useful with a variety of Lewis basic functional groups providing chelation assistance through an appropriate choice of catalyst and conditions. However, the requirement for a specific group to promote a reaction in a specific position limits the potential substrate scope of such reactions. Unfortunately, when a coordinating directing group is not utilized, positional selectivity is nearly always lost, leading to multiple constitutional isomers as products. Therefore, C–H functionalization reactions that can afford high and predictable positional selectivity without the requirement for a particular directing group have the potential to be very powerful.
When the group of Professor Tobias Ritter from Harvard University (USA) and Max-Planck-Institut für Kohlenforschung, Mülheim an der Ruhr (Germany) entered the field of C–H functionalization, they did so with the goal of developing useful C–H functionalization reactions that would not require the use of coordinating directing groups to provide chelation assistance.
Read here the full article for free Charge-Transfer-Directed Radical Substitution Enables para-Selective C–H Functionalization
