Imidazolin-2-iminato Ligand-Supported Titanium Complexes as Catalysts for the Synthesis of Urea Derivatives

摘要

A series of (mono) imidazolin-2-iminato ligand-supported titanium dimethylamido complexes (1a−c) having very short Ti−N bonds were synthesized and structurally characterized. The reactions of 1 with various heterocumelenes yielded mono-, bis-, and tris-insertion products depending on the electrophilicity of the central carbon atom of the heterocumelene under similar reaction conditions. Complex 1c was proved as moderately active catalyst for the production of urea derivative from isocyanate and various amines under mild conditions.