SYNTHESIS AND CHARACTERIZATION OF SUBSTITUTED CYCLOPENTADIENIDE LIGANDS THAT MAY FORM CHELATES OR METAL DIMERS

Nine different substituted cyclopentadienyl ligands, which have substi tuents that may either chelate or bridge to second metal center, have been prepared from nucleophilic substitution reactions of esters or al kyl halides with NaCp. The sodium or thallium salts of these ligands w ere isolated as solids and characterized by H-1 NMR. The alkyl halide and NaCp reaction proved to yield the purer salts of the ligands becau se of the milder reaction conditions. These salts were reacted futher with Mn(CO)(5)Br to form the corresponding manganese tricarbonyl deriv atives (i.e. (C(5)H(4)R)Mn(CO)(3); where R=C(O)CH2OCH3, C(O)CH2SCH3, C (O)CH2CH2SCH3, CH2CO2CH3, CH2CO2CH2CH3, CH2CH2CO2CH3, CH2CH2CO2CH2CH3, CH2CH2O2CCH3, and CH2CH2OCH3) and Na(C5H4C(O)CH2OCH3) was reacted wit h Co-2(CO)(8) to form (C5H4C(O)CH2OCH3)Co(CO)(2). The manganese and co balt compounds were characterized by elemental analysis, IR, H-1, and C-13 NMR spectra.