Ruthenium-carbonyl complexes with P/O or P/N donor ligands: Effect of the chelate ring size and donor atom

New ruthenium(II) coordination compounds possessing bidentate aminomethylphosphane ligands: synthesis, characterization and preliminary biological study in vitro

Addition of aminomethylphosphane P{CH2N(CH2CH2)2O}3 (), PPh2{CH2N(CH2CH2)2O} () or PPh2{CH2N(CH2CH2)2NCH2CH3} () to a methanolic solution of RuCl3 results in reduction of ruthenium(iii) ions giving finally ttt-[RuCl2()2] (), ttt-[RuCl2()2] () and ttt-[RuCl2()2] (). The synthesized complexes are the first examples of ruthenium(ii) coordination compounds possessing aminomethylphosphanes chelating via phosphorus and nitrogen atoms. They were fully characterized (NMR, ESI-MS, IR, elemental analysis, X-ray crystallography). Preliminary studies of the in vitro cytotoxicity on the A549 cell line (human lung adenocarcinoma) and interactions with human serum proteins (albumin and apotransferrin) showed moderate activity of the complexes. Interestingly, the P,N-chelation leads to formation of strained 4-membered Ru-P-C-N-Ru rings, which in the case of and undergo opening in the presence of CH3CN, which results in rearrangement to ctc-[RuCl2()2(CH3CN)2] () and ctc-[RuCl2()2(CH3CN)2] ().

Ruthenium(III) complexes containing bi- and tridentate phosphorus−nitrogen ligands

Air-stable RuIII complexes containing a bidentate aminophosphine ligand (PN) of the type mer-RuCl3(PN)(PR3) are made from the precursors RuCl3(PR3)2(DMA)·DMA (PN = o-diphenylphosphino-N,N′-dimethylaniline (P−N) and (R)-N,N′-dimethyl-1-[o-diphenylphosphinophenyl]ethylamine ((R)-AMPHOS); R = Ph, p-tolyl; DMA = N,N′-dimethylacetamide). With the tridentate bis[o-(N,N′-dimethylamino)phenyl]phenylphosphine (BNP), the product is mer-RuCl3(BNP) (3), while tris[o-(N,N′-dimethylaminophenyl)phosphine (TNP) is unreactive toward the precursor. Crystal structures of mer-RuCl3(PN)(PPh3), where PN is P−N (2a), (R)-AMPHOS (4a), and 3·CHCl3 are reported as well as those of (R)-AMPHOS, BNP, and TNP. The RuIII−aminophosphine complexes are the first monomeric RuIII species to be formed via the useful, easily synthesized, air-stable RuIII precursors RuCl3(PR3)2(DMA)·DMA (1a and 1b); complex 2a is formed also via reaction of HCl with trans-RuCl2(P−N)(PPh3). A crystal structure of mer,cis-RuCl3(DMA)2(PPh3)·DMA (1c), a side-product from the synthesis of the RuIII precursor, is also presented and is the first-reported complex of DMA with RuIII. Preliminary data show that the RuIII−aminophosphine complexes in DMA (a proton-accepting solvent) are reduced by H2 to RuII species that can react further to form an η2-H2 adduct and then a RuII-hydridochloro species.