Reduction of imine of samarium Schiff base chloride by sodium—Formation of a novel samarium complex through unprecedented C–C coupling and hydrogen transfer reaction

SmCl3 reacted with sodium salt of the Schiff base ligand L (L=3,5-Bu2t-2-O–C6H2CH–N-8-C9H6N) in a 1:2 molar ratio in THF to afford samarium Schiff base chloride L2SmCl(THF) (1). Treatment of complex 1 with excessive metallic sodium produced an unprecedented samarium complex [Na(DME)3][SmL3′Na(DME)] (2), in which three Schiff base ligands were trimerized to form the new ligand L3′ by the reductive coupling reactions of imine groups involving a rare coupling reaction of CN bond of quinoline ring with imine group of Schiff base ligand.

Graphical abstractReduction of samarium Schiff base chloride L2SmCl(THF) (1) (L=3,5-Bu2t-2-O–C6H2CH–N–8-C9H6N) with excessive metallic sodium produced an unprecedented samarium complex [Na(DME)3][SmL3′Na(DME)] (2), in which three Schiff base ligands were trimerized to form the new ligand L3′ by the reductive coupling reactions of imine groups involving a rare coupling reaction of CN bond of quinoline ring with imine group of Schiff base ligand.Figure optionsDownload full-size imageDownload as PowerPoint slide