Small Molecule Activation:Cleavage Of The C-CN Bond Of Acetonitrile

Cleavage of the C-C bond in acetonitrile remains a challenge in homogeneous conditions,because of the large C-C bond energy(133 kcal-mol-1)in small molecules.A simple method to active C-C bond in acetonitrile is reported in this paper.In the viewpoint of inorganic chemistry,the Cu(?)complex(1)can effectively active C-C bonds in acetonitrile to get Cu-CN complex in homogeneous conditions.To systematicly research C-C bond cleavage in acetonitrile,so the work was divided into two parts.First of all,the foudmental complex(Et4N)[Cu(pyN2Me2)(OH)])on basis of H2pyN2Me2(L1)was prepared.By the study of(Et4N)[Cu(pyN2Me2)(OH)]),the most optimal reaction condition was obtained as 2.5 mmol/L,NaOH,room temperature and 24 h.The complexes generating in this process were confirmed by IR spectroscopy.Structures of these complexes were characterized by means of single crystal X-ray crystallographic analysis.Secend,a range of ligands were synthesized by changing the substitutes and functional groups in H2pyN2Me2(L1).A series of Cu(?)complexes were prepared with these ligands.These complexs reacted with acetonitrile under the most optimal reaction condition.On basis of the results,it was concluded that cleavage of C-CN bond in acetonitrile was sensitive to steric hindrance of Cu(?)complexes.If the steric hindrance was a little larger,active ability of Cu(?)complexs could disappear.In addition,it was also concluded that OH was important to cleavage of C-CN bond in acetonitrile.The complexes prepared in the process were characterized by IR spectroscopy and single-crystal X-ray crystallographic analysis.Finally,the possible active mechanism was proposed.