Base Induced C-Cn Bond Cleavage At Room Temperature: A Convenient Method For The Activation Of Acetonitrile

An efficient and simple method was explored for the C-CN cleavage of acetonitrile in air at room temperature. The activation reaction was mediated by the mononuclear complex of [M-II(PyN2Ph2Me2)(OH)](1-)(M = Cu, Ni; PyN2Ph2Me2 = N,N'-bis(2,6-dimethylphenyl)-2,6-pyridinedicarboxamidate(2-)) in the presence of NaOH. Acetonitrile splits into cyanide and formaldehyde via the intermediate eta(2)-enaminemethide isomer species of [M-II-(CH=C=NH)] and [M-II-(N=C=CH2)]. A base-dioxygen induced reaction mechanism was proposed based on the crystal structures of intermediate complexes and organic adducts, which were characterized by X-ray crystallography, EPR spectroscopy, GC-MS techniques and DFT calculations. The nitrile-activated product [Cu-II-CN] was utilized as a cyanide source for the catalytic cyanation of iodobenzene, phenylboronic acid and 2-phenylpyridine.