The α-arylation of carbonyl compounds is generally accomplished under basic conditions, both under metal catalysis and via aryl transfer from the diaryl λ3-iodanes. Here, we describe an alternative metal-free α-arylation using ArI(O2CCF3)2 as the source of a 2-iodoaryl group. The reaction is applicable to activated ketones, such as α-cyanoketones, and works with substituted aryliodanes. This formal CH functionalization reaction is thought to proceed through a [3,3] rearrangement of an iodonium enolate. The final α-(2-iodoaryl)ketones are versatile synthetic building blocks.
An Alternative to the Classical α-Arylation: The Transfer of an Intact 2-Iodoaryl from ArI(O2CCF3)2
Angew. Chem. Int. Ed. 2014, 53, 11298-11301.