Inserted products of lithium silylquinolylamide dimers [{8-(2-R-C9H5N)N(Me3Si)}Li·OEt2]2 (R = H or Me) with dimethylcyanamide and their reactive derivatives with metal halides

Abstract

The insertion reactions of lithium silylquinolylamide dimers [{8-(2-R-C₉H₅N)N(Me₃Si)}Li·OEt₂]₂ (R = H, 1a; R = Me, 1b) with dimethylcyanamide afforded dimeric lithium 8-quinolylguanidinates [{8-(2-R-C₉H₅N)NC(NMe₂)N(SiMe₃)}Li]₂ (R = H, 2a; R = Me, 2b) with a cisoid arrangement of the ligands. Further reaction of 2b with MCl₂ (M = Co or Fe) formed the eight-membered binuclear metallic 8-quinolylguanidinate complexes [{8-(2-CH₃-C₉H₅N)NC(NMe₂)N(SiMe₃)}MCl]₂ (M = Fe, 3; Co, 4). The reaction of 2a with (MeC₅H₄)TiCl₃ afforded a centrosymmetric dimeric titanium(IV) complex [{8-(C₉H₆N)NC(NMe₂)N}Ti(MeC₅H₄)Cl]₂ (5) via a metathesis reaction and the elimination of SiMe₃Cl. The guanidinate ligand 2b was hydrolyzed with an equimolar amount of water, and reacted with (MeC₅H₄)TiCl₃ forming a monoligated half-titanocene compound {8-(2-CH₃-C₉H₅N)N(H)C(NMe₂)N}Ti(MeC₅H₄)Cl₂ (6). Therefore lithium silylquinolylamide dimers provided various coordinative multi-dentate ligands and resulted in a family of metal complexes.