Organometallic compounds of the lanthanides.: 158.: Alkenyl-functionalized cyclopentadienyl complexes of yttrium, samarium, and lutetium and their hydroboration

YCl3, SmCl3, and LuCl3 react with (tetramethylvinylcyclopentadienyl)lithium (1a), yielding (CH2=CHC5Me4)(2)Ln(mu-Cl)(2)Li(Et2O)(2) (Ln = Y (2a), Sm (2b), Lu (2c)). LuCl3 and the analogous potassium salt 1b form oligomeric [(CH2=CHC5Me4)(2)Lu(mu(3)-Cl)(2)K(THF)](n) (3). Methylation of the yttrium complex 2a with MeLi gives (CH2=CHC5Me4)(2)Y(mu-CH3)(2)Li(THF) (4). Hydroboration of the complexes 2a-c with 9-BBN results in the formation of (C8H14BCH2CH2C5Me4)(2)Ln(mu-Cl)(2)Li(THF)(2) (Ln = Y (5a), Sm (5b), Lu (5c)). The reaction Of YCl3 with 2 equiv of K[C5H4CH=C6H10] (6) or K[C5H4CH=CMe2] (10) affords the dimeric complexes [(C6H10=CHC5H4)(2)Y(mu-Cl)](2) (7) and [(Me2C=CHC5H4)(2)Y(mu-Cl)](2) (11), whereas SMCl3 reacts with 2 equiv of 6 or 10, yielding the tris(cyclopentadienyl) derivatives (C6H10=CHC5H4)(3)Sm(THF) (9) and (Me2C=CHC5H4)(3)Sm(THF) (13), respectively. Methylation of 7 with MeLi yields unstable [(C6H10=CHC5H4)(2)Y(mu-CH3)](2) (7a). SmI2 and 6 react with formation Of (C6H10=CHC5H4)(2)Sm(THF)(2) (8). Hydrolysis during crystallization of 11 caused by some water in the solvent leads to decomposition, forming the oxygen-bridged complex [(Me2C=CHC5H4)(2)Y(Et2O)](2)(mu-0) (12). The ansa-lanthanidocene chloride [H2C=C(CH2C5H4)(2)]LuCl(THF) (15) was prepared from LuCl3 and the new ligand K-2[H2C=C(CH2C5H4)(2)] (14). The structures of 2a, 3, 5b, 7, and 12 were determined by single-crystal X-ray diffraction.