Rhodium-Catalyzed Directing-Group-Assisted Aldehydic C-H Arylations with Aryl Halides

A rhodium-catalyzed general protocol for the directing-group-assisted arylation of aromatic aldehydic C-H bonds was developed. This method involves either hydroxy- or amino-group-directed aldehyde C-H arylation with various aryl halides. A broad synthetic scope for the preparation of 2-hydroxybenzophenones was established with electronically variant salicylaldehydes and aryl halides with chemo- and regioselective possibilities. The developed protocol was also applied in the synthesis of medicinally important 3-salicyloylpyridines in high yields.