CYCLOPALLADATED COMPOUNDS DERIVED FROM FERROCENYLIMINES - CRYSTAL-STRUCTURE OF [PD((ETA-5-C5H5)FE[ETA-5-C5H3CH=N(CH2)2PH])CL(PET3)]

Reactions of ferrocenylimines of general formula [Fe(eta-5-C5H5){eta-5-C5H4CH=N(CH2)nPh}] (n = 1 1a or 2 1b) with palladium(II) salts have been studied. The dimeric cylopalladated complexes [{Pd[(15-C5H5)Fe{eta-5-C5H3CH=N(CH2)nPh}]Cl}2] 2a and 2b were obtained when the reactions were carried out in the presence of sodium acetate and using Na2[PdCl4] as starting material. Addition of phosphine ligands PR3 (R = Ph or Et) or 1,2-bis(diphenylphosphino)ethane (dppe) to acetone suspensions of these dinuclear compounds produced the more soluble mononuclear complexes [Pd{(eta-5-C5H5)Fe[eta-5-C5H3CH=N(CH2)nPh])Cl(PR3)] with R = Ph (3a and 3b) and Et (4a and 4b) and [Pd{(eta-5-C5H5)Fe[eta-5-C5H3CH=N(CH2)nPh]}(dppe)]Cl (5a and 5b). Proton and P-31 NMR spectroscopic studies on these compounds confirm the formations of endo five-membered metallocycles. Mossbauer spectra of compounds 1b-5b have also been recorded. The first crystal structure of a cyclopalladated complex derived from ferrocenylimines has been determined. The compound [Pd{(eta-5-C5H5)Fe(eta-5-C5H3CH=NCH2CH2Ph)}Cl(PEt3)] 4b is monoclinic, space group P2(1)/a, with a = 15.944(3), b = 12.425(2), c = 1 2.682(2) angstrom, beta = 100.19(2)-degrees and Z = 4. The structure confirms the formation of an endo five-membered metallocycle on the ferrocene moiety.