Synthesis and characterization of novel platinum group metal complexes of bis[2-(diphenylphosphino)ethyl]amine

Abstract

A mixed donor tridentate ligand bis[2-(diphenylphosphino)ethyl]amine (DPEA) was synthesized in its hydrochloride form by a modified procedure and characterized by ¹H, ¹³C and ³¹P NMR spectral data. Reaction of RhCl(CO)(PPh₃)₂ with DPEA · HCl and NaBPh₄ in methanol gave the cationic Rh(I) complex [Rh(DPEA)PPh₃IBPh₄ but the reaction of IrCl(CO)(PPh₃)₂ with DPEA·HCl in boiling benzene gave a unique complex, [Ir(H)(Cl)(CO)(DPEA)]Cl, in which five different donor atoms are coordinated to the single Ir(III) ion. A neutral, RH(III) complex of the composition [RhCl₃(DPEA)] was prepared by the reaction of RhCl₃·xH₂O with DPEA·HCl in methanol. Reaction of PdCl₂(COD) with DPEA·HCl in benzene or methanol gave the cationic complex [PdCl(DPEA)]Cl the above reaction conducted in benzene-acetone-methanol mixture gave the 1:2 complex [Pd(DPEA)₂]Cl₂. A novel trinuclear Pt(II) complex of the composition [Pt₃Cl₃(DPEA)₃]Cl₃ was prepared by the reaction of K₂PtCl₄ and DPEA·HCl in water-acetone mixture. Reaction of K₂PtCl₄, DPEA·HCl and NH₄PF₆ in water ethanol mixture gave the binuclear, cationic complex, [Pt₂(DPEA)₃](PF₆)₄. All the complexes were characterized by elemental analysis, conductivity, ¹H and ³¹P NMR spectral data.