Pentadienyl-Metal-Phosphine Chemistry. 17.1 Syntheses, Structures, and Spectroscopy of Pentadienyl-Ruthenium-Phosphine Complexes

  • J. R. Bleeke
  • , D. J. Rauscher

Research output: Contribution to journalArticlepeer-review

31 Scopus citations

Abstract

The reaction of RuCl2(PPh3)3 with pentadienyltributyltin produces (η5-pentadienyl)RuCl(PPh3)2(1), which serves as a convenient starting material for the synthesis of a large family of new pentadienyl-ruthenium-phosphine complexes. Treatment of 1 with 1 equiv of PMe3, PMe2Ph, PEt3, or PEt2Ph produces the mixed-phosphine complexes (η5-pentadienyl)RuCl(PR3)(PPh3) (2a, PR3 = PMe3; 2b, PR3= PMe2Ph; 2c, PR3 = PEt3; 2d, PR3 = PEt2Ph). Compound 2c crystallizes in the monoclinic space group P21/c with a = 11.435 (2) Å, b = 13.770 (4) Å, c = 18.237 (5) Å, β = 109.04 (2)°, V = 2715 (1) Å3, and Z = 4. This complex adopts a pseudooctahedral coordination geometry with the PEt3 ligand residing under the open “mouth” of the pentadienyl ligand and the PPh3 and Cl groups lying under the pentadienyl “edges”. Treatment of 1 with 2 equiv of PEt3, PEt2Ph, or PEtPh2 produces (η5-pentadienyl)RuCl(PR3)2(3c, PR3 = PEt3; 3d, PR3 = PEt2Ph; 3e, PR3 = PEtPh2). (η5-Pentadienyl)RuCl(PMe2Ph)2(3b) is obtained cleanly by reacting 2b with one additional equivalent of PMe2Ph. (η5-Pentadienyl)RuCl(PEt3) (3c) [monoclinic, Cc, a = 28.094 (7) Å, b = 10.003 (2) Å, c = 15.134 (3) Å, β = 98.54 (2)°, V = 4205 (2) Å3, Z = 8] and (η5-pentadienyl)RuCl(PEt2Ph)2(3d) [orthorhombic, P212121, a = 16.848 (7) Å, b = 19.409 (4) Å, c = 7.867 (1) Å, V = 2572 (1) Å3, Z = 4] have been structurally characterized. Both complexes adopt pseudooctahedral coordination geometries in which one phosphine resides under the pentadienyl “mouth” while the other phosphine and the chloro ligand lie under the pentadienyl “edges”. Treatment of 1 with 3 equiv of PMe3 produces (η3-pentadienyl)RuCl(PMe3)3(4a). (η3-Pentadienyl)RuCl(PMe2Ph)3(4b) is obtained upon treatment of 2b with 2 equiv of PMe2Ph. 4a crystallizes in the monoclinic space group P21/n with a = 9.628 (3) Å, b = 13.662 (3) Å, c = 15.667 (4) Å, β = 91.59°, V = 2060 (1) Å3, and Z = 4. 4a's coordination geometry is pseudooctahedral with Cl and C3 of the pentadienyl ligand, the three phosphorus atoms, and the chlorine atom occupying the six coordination sites. The η3-pentadienyl ligand adopts a W-shaped syn geometry. Both 4a and 4b react with Ag+O3SCF3- or Me+O3SCF3- to yield [(η5-pentadienyl)Ru(PR3)3]+O3SCF3-(5a, PR3 = PMe3; 5b, PR3 = PMe2Ph). 5a crystallizes in the monoclinic space group P21/m with a = 8.622 (2) Å, b = 11.302 (4) Å, c = 12.676 (2) Å β = 103.22 (1)°, V = 1202.6 (6) Å3, and Z = 2. It exhibits pseudooctahedral coordination geometry with one PMe3 ligand under the open pentadienyl “mouth” and the other PMe3 ligands under the pentadienyl “edges”. Compounds 1, 3, and 5 undergo dynamic processes in solution involving rotation of their pentadienyl groups with respect to the metal-ligand framework. ΔG's for these processes have been determined from line-shape simulations of the variable-temperature 31P NMR spectra.

Original languageEnglish
Pages (from-to)2328-2339
Number of pages12
JournalOrganometallics
Volume7
Issue number11
DOIs
StatePublished - Nov 1988

Fingerprint

Dive into the research topics of 'Pentadienyl-Metal-Phosphine Chemistry. 17.1 Syntheses, Structures, and Spectroscopy of Pentadienyl-Ruthenium-Phosphine Complexes'. Together they form a unique fingerprint.

Cite this