Organotin(<scp>iv</scp>) compounds catalyzed cyanide-free synthesis of α-iminonitriles

Two polydentate pro-ligands (H2L1 and H3L2) have been reacted with different organotin(IV) halides such as Ph₂SnCl₂, (<i>t</i>-Bu)₂SnCl₂, and (<i>n</i>-Bu)₂SnCl₂ to synthesize six organotin(IV) compounds, [R₂Sn(L¹)] (R = Ph (1), <i>t</i>-Bu (2), <i>n</i>-Bu (3)) and [R₂Sn(HL²)] (R = Ph (4), <i>t</i>-Bu (5), <i>n</i>-Bu (6)), respectively. All organotin(IV) compounds were characterized by FT-IR spectroscopy, ¹H, ¹³C{¹H}, and ¹¹⁹Sn{¹H} NMR spectroscopy, HR-MS spectrometry, and single-crystal X-ray diffraction analysis. The single-crystal X-ray diffraction analyses reveal that all compounds contain a penta-coordinated tin atom except 1. Compound 1 is hexacoordinated. All organotin compounds show catalytic efficiency towards the synthesis of α-iminonitriles, with a maximum yield of up to 88%. The α-iminonitriles are synthesized from <i>trans</i>-β-nitrostyrene derivatives and 2-aminopyridine derivatives without using any cyanating agent.