Single-crystal structure determinations on trans- and trans-[OsC12(PPh,H),J~CH,C12 Now report the synthesis and redox studies of Īnd, (M = Ru or Os, R = Ph or C6Hll). Studies were intended to establish the susceptibility of PR,HĪnd PRH, complexes to spontaneous deprotonation we haveĮxtended this work to ruthenium and osmium complexes. Of Pd" and Pt" undergo spontaneous deprotonation to give the Solution over very long period^.^ In contrast, PPh,H complexes NMR spectroscopy to be stable with respect to deprotonation in We have recently reported the complex cations (M = Pd or Pt) which were shown by multinuclear Recently reported the first example of an agostic Pd Poorly studied,-* and early studies indicated that upon coordination the P-H bonds become unstable to deprotonation Good yields initially with the PH groups intact, therebyĪllowing controlled deprotonation and further reaction.ĭespite the vast literature describing tertiary phosphine (PR,)Ĭo-ordination, PRH, and PR,H ligation have been relatively The PH groups, it is essential that they can be synthesised in To be useful for further functionalisation, such as alkylation, at Order for these primary and secondary phosphine complexes In their template syntheses of tetraphosphine macrocycles. Offer the possibility of further functionalisation following coordination, as shown for example by Stelzer and co-workers ' Our interest arises from the fact that they Primary and secondary phosphines (PRH, and PR,H) with We have been investigating the co-ordination chemistry of Reversible oxidation in each case, which is assigned to a M"-M"' redox couple. With the exception of (irreversible),Ĭyclic voltammetric studies on the complexes trans- and trans- show a The crystal-structure determination of trans- *CH,CI, showed two independent half Octahedral arrangement seen in trans- compared to trans- ~0.5CHC13. The lower steric demands of the PPhH, ligands compared to PPh,H are reflected in the more regular It confirms a transĪrrangement of the CI- ligands with the Ru" occupying a crystallographic inversion centre with four The crystal structure of trans- has been determined. Prolonged standing of trans in CH,CI, solution led to partial isomerisation to the cis isomer a s confirmed by 31PN M R Species exist a s trans isomers in solution and the integrity of the PH functions. Ultraviolet-visible and 31P N M R spectroscopic studies confirm that these In degassed refluxing EtOH solution (or EtOH-water for 0 s ) gave and in Reaction of RuCI3.3H,O or, with 5-7 molar equivalents of PR,H ( R = Ph or C,H,) or PPhH, Roche Research Centre, Welwyn Garden City AL7 3AY, UK S i m p s o dĪ Department of Chemistry, The University of Edinburgh, West Mains Road, Edinburgh EH9 3JJ, UKĭepartment of Chemistry, The University of Southampton, Highfield, Southampton SO9 5NH, U K Single-crystal Structures of trans- andĪlexander J. Synthesis and Redox Studies on Ruthenium and OsmiumĬomplexes with Primary and Secondary Phosphines. Downloaded by State University of New York at Stony Brook on 06:32:32. These are coupled to highly efficient Broyden and Pulay density mixing schemes to speed up the self-consistency cycle.View Article Online / Journal Homepage / Table of Contents for this issue To determine the electronic ground state, VASP makes use of efficient iterative matrix diagonalisation techniques, like the residual minimisation method with direct inversion of the iterative subspace (RMM-DIIS) or blocked Davidson algorithms. The interactions between the electrons and ions are described using norm-conserving or ultrasoft pseudopotentials, or the projector-augmented-wave method. Furthermore, Green's functions methods (GW quasiparticles, and ACFDT-RPA) and many-body perturbation theory (2nd-order Møller-Plesset) are available.Ĭentral quantities, like the one-electron orbitals, the electronic charge density, and the local potential are expressed in plane wave basis sets. Hybrid functionals that mix the Hartree-Fock approach with DFT are implemented as well. VASP computes an approximate solution to the many-body Schrödinger equation, either within density functional theory (DFT), solving the Kohn-Sham equations, or within the Hartree-Fock (HF) approximation, solving the Roothaan equations. electronic structure calculations and quantum-mechanical molecular dynamics from first principles. It is used for atomic scale materials modelling, e.g. VASP is an ab initio simulation package based on DFT.
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