Organometallic Compounds of the Lanthanides. 158.¹ Alkenyl-Functionalized Cyclopentadienyl Complexes of Yttrium, Samarium, and Lutetium and Their Hydroboration

YCl 3, SmCl 3, and LuCl 3 react with (tetramethylvinylcyclopentadienyl)lithium ( 1a ), yielding (CH 2 CHC 5 Me 4 ) 2 Ln( μ -Cl) 2 Li(Et 2 O) 2 (Ln = Y ( 2a ), Sm ( 2b ), Lu ( 2c )). LuCl 3 and the analogous potassium salt 1b form oligomeric [(CH 2 CHC 5 Me 4 ) 2 Lu( μ 3 -Cl) 2 K(THF)] n ( 3 ). Methylation of the yttrium complex 2a with MeLi gives (CH 2 CHC 5 Me 4 ) 2 Y( μ -CH 3 ) 2 Li(THF) ( 4 ). Hydroboration of the complexes 2a − c with 9-BBN results in the formation of (C 8 H 14 BCH 2 CH 2 C 5 Me 4 ) 2 Ln( μ -Cl) 2 Li(THF) 2 (Ln = Y ( 5a ), Sm ( 5b ), Lu ( 5c )). The reaction of YCl 3 with 2 equiv of K[C 5 H 4 CH C 6 H 10 ] ( 6 ) or K[C 5 H 4 CH CMe 2 ] ( 10 ) affords the dimeric complexes [(C 6 H 10 CHC 5 H 4 ) 2 Y( μ -Cl)] 2 ( 7 ) and [(Me 2 C CHC 5 H 4 ) 2 Y( μ -Cl)] 2 ( 11 ), whereas SmCl 3 reacts with 2 equiv of 6 or 10, yielding the tris(cyclopentadienyl) derivatives (C 6 H 10 CHC 5 H 4 ) 3 Sm(THF) ( 9 ) and (Me 2 C CHC 5 H 4 ) 3 Sm(THF) ( 13 ), respectively. Methylation of 7 with MeLi yields unstable [(C 6 H 10 CHC 5 H 4 ) 2 Y( μ -CH 3 )] 2 ( 7a ). SmI 2 and 6 react with formation of (C 6 H 10 CHC 5 H 4 ) 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 [(Me 2 C CHC 5 H 4 ) 2 Y(Et 2 O)] 2 ( μ -O) ( 12 ). The ansa -lanthanidocene chloride [H 2 C C(CH 2 C 5 H 4 ) 2 ]LuCl(THF) ( 15 ) was prepared from LuCl 3 and the new ligand K 2 [H 2 C C(CH 2 C 5 H 4 ) 2 ] ( 14 ). The structures of 2a, 3, 5b, 7, and 12 were determined by single-crystal X-ray diffraction.