Trans-influences in mononuclear cyclopalladated compounds containing a #sigma#(pd-C_sp2, ferrocene) bond. X-ray crystal structure of[Pd{[(#eta#~5-C_5H_3)-CH=N-CH_2-C_6H_5]Fe(#eta#~5-C_5H_5)}(X)(PPh_3)] with X~- = Br~- and I~-

摘要

The syntheses, characterization and study of the properties of cyclopalladated comkpounds of general formula: [Pd{[(#eta#~5-C_5H_3)-CH=N-CH_2-C+6H_5]Fe(#eta#~5-C_5H_5)}(X)(PPh_3)] with X~- = Cl~-, Br~-, I~-, CN~- SCN~- or AcO~- are reported. Compounds with X~- = Br~- and I~- were characterized by X-ray diffraction, and their crystal structures revealed the existence of a weak C-H···X interaaction involving one of the -CH_2-type hydrogen atoms bond to the imine nitrogen. Comparison of the spectroscopic properties of these compuonds has allowed us to elucidate the influence of the monoanionic ligand, X~-, on a trans-arrangement to the metallated carbon atom upon the environment of the iron(II). Theoretical studies based on the semiempirical PM3(tm) were also been caaried out to clarify the effect produced by the X~- ligand on the ring current of the metallated C_5H_3 ring of the ferrocenyl fragment.