Efficient Large‐Scale Synthesis of Picolinic Acid‐Derived Nickel( II ) Complexes of Glycine

An efficient, large‐scale method for the preparation of 2‐[N‐(α‐picolyl)amino]acetophenone (PAAP) and 2‐[N‐(α‐picolyl)amino]benzophenone (PABP), the hitherto unknown 4‐methyl‐2‐[N‐(α‐picolyl)amino]benzophenone (4‐Me‐PABP) and 4‐nitro‐2‐[N‐(α‐picolyl)amino]benzophenone (4‐NO2‐PABP), and their corresponding NiII complexes with glycine is described. The key step of the method is the formation of the mixed anhydrides derived from o‐picolinic acid and ethyl chloroformate or p‐toluenesulfonyl chloride. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)