The reactions of 1,3-diisopropyl-4,5-dimethylimidazolin-2-imine (Im i Pr NH) with the trimethylsilylmethyl (neosilyl) complexes [M(CH 2 SiMe 3 ) 3 (THF) 2 ] (M=Sc, Y, Lu) in a 3:1 ratio afforded tetramethylsilane (TMS) and the dinuclear imidazolin-2-iminato complexes [M 2 (Im i Pr N) 6 (THF) n ] (1a, M=Sc, n=0; 1b, M=Y, n=1; 1c, M=Lu, n=1), in which the metal atoms are bridged by two μ 2 -Im i Pr N ligands. 1a crystallized from THF/pentane solution to afford a solvent-free, centrosymmetric, dimeric complex, in which both scandium atoms attain a coordination number of four; three uncoordinated THF per dimer are observed. In contrast, the X-ray crystal structures of 1b·2THF and 1c·2THF reveal the formation of unsymmetric THF solvate complexes that contain one THF ligand and therefore both four- and five-coordinated rare earth metal atoms; other THF molecules are non-coordinating. The reaction of [Y(CH 2 SiMe 3 ) 3 (THF) 2 ] with three equivalents of the sterically more demanding 1,3-di-tert-butylimidazolin-2-imine (Im t Bu NH) afforded the mononuclear complex [Y(Im t Bu N) 3 (THF) 2 ] (2) with a five-coordinated yttrium atom, as indicated by X-ray diffraction analysis of 2·2THF.