Pd(II)-Catalyzed Asymmetric Addition of Arylboronic Acids to Aliphatic N-Carbamoyl Hydrazones

Catalysts generated by combinations of Pd(TFA)(2) and pyridine-hydrazone ligands have been applied to 1,2 addition of arylboronic acids to aliphatic N-carbamoyl (Cbz) hydrazones, affording protected alpha-aryl monoalkylhydrazines with high enantioselectivities (37-99% ee). Subsequent removal of the benzyloxy carbonyl protecting group provides a direct entry to free monosubstituted hydrazines, key building blocks for the synthesis of appealing 1,2-diaza-heterocycles, aminoacid derived hydrazides and other pharmacophores thereof.

Automated summary

Catalysts generated by combinations of Pd(TFA)(2) and pyridine-hydrazone ligands have been successfully applied to the addition of arylboronic acids to aliphatic N-carbamoyl hydrazones, providing protected alpha-aryl monoalkylhydrazines with high enantioselectivities. The resulting monosubstituted hydrazines can serve as key building blocks for the synthesis of various organic compounds.