Manganese-Pincer-Catalyzed Nitrile Hydration, α‑Deuteration, and α‑Deuterated Amide Formation via Metal Ligand Cooperation
journal contributionposted on 2021-08-03, 11:36 authored by Quan-Quan Zhou, You-Quan Zou, Sayan Kar, Yael Diskin-Posner, Yehoshoa Ben-David, David Milstein
A simple and efficient system for the hydration and α-deuteration of nitriles to form amides, α-deuterated nitriles, and α-deuterated amides catalyzed by a single pincer complex of the earth-abundant manganese capable of metal–ligand cooperation is reported. The reaction is selective and tolerates a wide range of functional groups, giving the corresponding amides in moderate to good yields. Changing the solvent from tert-butanol to toluene and using D2O results in formation of α-deuterated nitriles in high selectivity. Moreover, α-deuterated amides can be obtained in one step directly from nitriles and D2O in THF. Preliminary mechanistic studies suggest the transformations contributing toward activation of the nitriles via a metal–ligand cooperative pathway, generating the manganese ketimido and enamido pincer complexes as the key intermediates for further transformations.