Amino Acid Ligands for Ruthenium(II)-Catalyzed C-H Arylation of Aryltetrazoles with Chlorides: Expedient Access to Antihypertension Drugs

Versatile ruthenium(II) complexes derived from amino acids enabled the first general C-H arylations of aryltetrazoles with inexpensive aryl chlorides. The user-friendly Piv-Val-OH-based ruthenium(II) catalyst was characterized by a broad substrate scope, excellent functional group tolerance, and high catalytic activity. Thereby, the ruthenium(II) catalysis set the stage for the step-economical preparation of the blockbuster antihypertension drug Valsartan, while displaying unique robustness in the C-H arylation regime.