ORGANOMETALLIC COMPOUNDS OF THE LANTHANIDES .110. DONOR-FUNCTIONALIZED CHIRAL CYCLOPENTADIENYL COMPLEXES OF CALCIUM, SAMARIUM(II), AND YTTERBIUM(II) - A NEW CLASS OF CHIRAL METALLOCENES

Twelve optically active metallocene complexes of Ca, Sm(II), and Yb(II ) containing cyclopentadienyl systems with a chiral N- or O-substitute d side chain as ligands are described. Specifically, the ligand system s (S)-(2-methoxypropyl)cyclopentadienyl ((S)-C5H4CH2CH(Me)OMe)) and (S )-(2-methoxy-2-phenylethyl)cyclopentadienyl ((S)-C5H4CH2CH(Ph)OMe)) an d the novel (S)-[2-(dimethylamino)propyl]cyclopentadienyl ((S)-C5H4CH2 CH(Me)NMe(2))) and -[2-(dimethylamino)-1-phenylethyl]cyclopentadienyl ((S)-C5H4CH(Ph)CH(2)NMe(2))) systems were employed. The starting mater ials for their synthesis are ethyl (S)-(-)-lactate, (R)-(-)-2-methoxy- 2-phenylethanol, (S)-(+)-2-amino-1-propanol, and (R)-(-)-2-phenylglyci nol, respectively. Each of the cyclopentadienyl systems was converted by a 2:1 reaction of the potassium salt with the metal diiodide into t he corresponding metallocene, [M{(S)-eta(5):eta(1)-C5H4(CH2CH(R)OMe)}( 2)] (R=Me, M=Ca (1a), Sm (1b), Yb (1c); R=Ph, M=Ca (3a), Sm (3b), Yb ( 3c)), [M{(S)-eta(5):eta(1)-C5H4(CH2CH(Me)NMe(2))}(2)] (M=Ca (2a), Sm ( 2b), Yb (2c)), and [M{(S)-eta(5):eta(1)-C5H4(CH(Ph)CH(2)NMe(2))}(2)] ( M=Ca (4a), Sm (4b), Yb (4c)). The novel compounds have been characteri zed by C, H, N analysis, mass spectrometry, NMR spectroscopy, and opti cal rotation. Additionally, an X-ray structural analysis of 2c, 3a, an d 4a was performed.