title: Construction of a monoanionic S,N,S-pincer ligand with a pyrrole core by sequential [1,2] phospho-Fries rearrangement. Characterization of palladium and silver coordination complexes.
abstract: The synthesis of an S,NH,S-pincer ligand possessing a pyrrole core and two O,O-diethylthiophosphonyl groups to design P=S lateral coordination sites is reported. The synthetic procedure to produce this ligand makes use of the nitrogen atom of the pyrrole heterocycle to successively functionalize the ortho-positions with the two O,O-diethylthiophosphonyl moieties. The ortho-functionalization arises from a repetition of a [1,2] base-induced rearrangement allowing the transformation of O,O-diethyl-N-pyrollylthiophosphoramidate to ortho-thiophosphonate. The coordination properties of this tridentate S,NH,S-ligand have been investigated with silver and palladium metals. Reaction of the monoanionic S,N,S-pincer ligand 4 (O,O,O,O-tetraethylpyrrol-2,5-yl-dithiophosphonate) with PdCl(2)(MeCN)(2) at room temperature in the presence of triethylamine gives rise to the formation of the eta(3)-complex [Pd(eta(3)-4')Cl] 5. Ligand 4 also reacts with silver oxide in dichloromethane to produce complex which, in the solid state, exists as a tetramer involving an almost linear arrangement of four silver atoms.
authors.affiliation: Université Européenne de Bretagne, Université de Brest, CNRS UMR 6521, CEMCA, IFR 148 ScInBios, 6 Avenue Le Gorgeu, 29238, Brest, France.
authors.forename: Aurore
authors.initials: A
authors.lastname: Fraix
authors.forename: Martin
authors.initials: M
authors.lastname: Lutz
authors.forename: Anthony L
authors.initials: AL
authors.lastname: Spek
authors.forename: Robertus J M
authors.initials: RJ
authors.lastname: Klein Gebbink
authors.forename: Gerard
authors.initials: G
authors.lastname: van Koten
authors.forename: Jean-Yves
authors.initials: JY
authors.lastname: Salaün
authors.forename: Paul-Alain
authors.initials: PA
authors.lastname: Jaffrès
mesh_terms: D000838:Anions / Q000737:chemistry*; D056831:Coordination Complexes / Q000138:chemical synthesis / Q000737:chemistry*; D018360:Crystallography, X-Ray; D008024:Ligands; D008968:Molecular Conformation; D063086:Organothiophosphates / Q000737:chemistry; D010165:Palladium / Q000737:chemistry*; D011758:Pyrroles / Q000737:chemistry*; D012834:Silver / Q000737:chemistry*; D013696:Temperature
chemical_list: D000838:Anions; D056831:Coordination Complexes; D008024:Ligands; D063086:Organothiophosphates; D011758:Pyrroles; C059014:O,O-diisopropyl dithiophosphate; D012834:Silver; D010165:Palladium