65567-06-8Relevant articles and documents
Atypical and Asymmetric 1,3-P,N Ligands: Synthesis, Coordination and Catalytic Performance of Cycloiminophosphanes
Rong, Mark K.,Holtrop, Flip,Bobylev, Eduard O.,Nieger, Martin,Ehlers, Andreas W.,Slootweg, J. Chris,Lammertsma, Koop
supporting information, p. 14007 - 14016 (2021/09/09)
Novel seven-membered cyclic imine-based 1,3-P,N ligands were obtained by capturing a Beckmann nitrilium ion intermediate generated in situ from cyclohexanone with benzotriazole, and then displacing it by a secondary phosphane under triflic acid promotion. These “cycloiminophosphanes” possess flexible non-isomerizable tetrahydroazepine rings with a high basicity; this sets them apart from previously reported iminophophanes. The donor strength of the ligands was investigated by using their P-κ1- and P,N-κ2-tungsten(0) carbonyl complexes, by determining the IR frequency of the trans-CO ligands. Complexes with [RhCp*Cl2]2 demonstrated the hemilability of the ligands, giving a dynamic equilibrium of κ1 and κ2 species; treatment with AgOTf gives full conversion to the κ2 complex. The potential for catalysis was shown in the RuII-catalyzed, solvent-free hydration of benzonitrile and the RuII- and IrI-catalyzed transfer hydrogenation of cyclohexanone in isopropanol. Finally, to enable access to asymmetric catalysts, chiral cycloiminophosphanes were prepared from l-menthone, as well as their P,N-κ2-RhIII and a P-κ1-RuII complexes.
Electrocatalytic property, anticancer activity, and density functional theory calculation of [NiCl(P^N^P)]Cl.EtOH
Mohammadnezhad, Gholamhossein,Abad, Saeed,Farrokhpour, Hossein,G?rls, Helmar,Plass, Winfried
, (2020/12/01)
This study describes the electrocatalytic, anticancer, and density functional theory (DFT) studies of a nickel complex, [NiCl(P^N^P)]Cl.EtOH, based on a neutral P^N^P-type pincer ligand (P^N^P = bis[(2-diphenylphosphino)ethyl]amine). The ligand was synthesized without time-consuming and costly amine protection. It was characterized by 1H NMR, 31P NMR, Fourier transform infrared (FT-IR), UV–vis, and single-crystal X-ray diffraction. The complex was isolated as a solvated chloride salt and characterized by FT-IR, UV–visible, 1H NMR, 13C NMR, and 31P NMR spectroscopies as well as single-crystal X-ray diffraction and CHN analysis. The ligand and complex crystallized in a monoclinic P21/c space group. The molecular structure of the complex contains a four-coordinated distorted nickel ion with square-planar geometry. The electrocatalytic hydrogen ion reduction was studied for the nickel complex in an acidic non-aqueous medium. Cyclic voltammetry studies showed that this complex is an efficient electrocatalyst for hydrogen evolution at the potential of the Ni(II/I) couple. As a potential anticancer agent, the biological activities of the Ni complex were tested against two human cancer cell lines (MCF7 and HT29). The IC50 results demonstrated that the nickel complex has better cytotoxic activity than cis-platin against the human breast cancer cell (MCF7) line. DFT calculations were performed to study the kinetics and thermodynamics of the pincer ligand's synthetic procedure and its Ni complex. Time-dependent DFT calculations were performed to calculate the pincer ligand's UV–vis spectra and the complex, which was in agreement with the experimental data. To assign the calculated UV spectra, molecular orbital calculations were performed. Finally, a modified mechanism was proposed for the electrocatalytic hydrogen ion reduction by [Ni(P^N^P)Cl]Cl.EtOH. The theoretical calculations showed that the cycle is thermodynamically favorable.
Synthesis, structural and toxicological investigations of quarternary phosphonium salts containing the P-bonded bioisosteric CH2F moiety
Dubovnik, Sviatlana,Karaghiosoff, Konstantin,Kornath, Andreas,Reichel, Marco,Roidl, Andreas,Unger, Cornelia
, p. 14306 - 14315 (2020/09/03)
Tertiary alkyl, aryl or amino phosphines PR3 (R = Me, nBu, C2H4CN, NEt2) and the bis[(2-diphenylphosphino)phenyl]ether (POP) were allowed to react with fluoroiodomethane to produce fluoromethyl phosphonium salts in yields between 60-99%. The compounds were characterized by vibrational and NMR spectroscopy and in most cases also by single crystal X-ray diffraction. Diphenyl(fluoromethyl) phosphine was synthesized as a mixed aryl-alkyl-phosphine and the TEP value (Tolman electronic parameter) was determined in order to explain its low reactivity. The molecular and crystal structures of the new fluoromethyl phosphonium salts [R3PCH2F]I with R = Me, C2H2CN and NEt2 as well as of the salt resulting from the fluoromethylation of POP provided additional information on the structural behavior of the bioisoster CH2F group bonded to phosphorus. Hydrogen bonding in the crystal is compared with that observed in the crystal structure of PPh3CH2FI. The toxicity of the sufficiently water soluble salt [Me3PCH2F]I was investigated and the toxicological effect of the CH2F group was compared to that of the bioisoster CH2OH group in THPS. This journal is
