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Manfred Scheer Coordination Chemistry of Phosphorous Containing Compounds Angela Dann May 8, 2006 Research Interests Supramolecular Arrays Fullerene-like nanoballs Heteronuclear clusters with main group metal incorporation 1-Dimensional and 2-Dimensional Polymers Complexes Containing a TungstenPhosphorous Triple Bond Fullerene-like Nanoballs [CpxFe(η5-P5)] + CuIX Cpx = η5-C5Me5, η5-C5Me4Et X = Br, Cl, I Soluble nanoballs form along with insoluble 1-D and 2-D polymers Contain 90 non-carbon atoms Eur. J. Inorg. Chem. 2005, 4023 Reaction Conditions Mixed solvent system: CH3CN and CH2Cl2 Soluble product formed upon increasing dilution (15 mmol/L 7.5 mmol/L) Negligible amount of polymer formed with dilution of 3.75 mmol/L 2:1 optimum stoichiometry of CuBr:[CpxFe(η5P5)] x = η5-C5Me5 or η5-C5Me4Et Eur. J. Inorg. Chem. 2005, 4023 Structural Analysis Black crystals Broad 31P NMR chemical shifts at 66 and 68 ppm X-ray diffraction – P atoms coordinate to Cu atoms on both sides of CuBr Core symmetry is D5h Ethyl groups attached to Cp decrease symmetry to Cs X-ray Structure Eur. J. Inorg. Chem. 2005, 4023 Heteronuclear Clusters Incorporating Main Group Elements Elevated synthetic and applied potential Increased stability upon addition of main group element 1st example of electrophilic addition of a Cp*M2+ unit to an Fe2Q face of a cluster M = Rh, Ir Q = S, Se, Te Journal of Cluster Science 2003, 14, 299 Reaction Scheme [Fe3(μ3-Q)(CO)9][NEt4]2 + [Cp*M(CH3CN)3][CF3SO3]2 M = Rh, Ir Q = S, Se, Te Journal of Cluster Science 2003, 14, 299 Initial Attempts Attachment at edge or corner rather than at the Fe2Q face Journal of Cluster Science 2003, 14, 299 Addition to the Fe2Q Face Two possible reaction pathways Closo structure with a μ3-Q ligand – 60e Butterfly-shaped structure with a μ4-Q ligand – 62e M = Rh – butterfly-shaped structure only M = Ir – major product with butterfly-shaped structure, minor product with closo structure Journal of Cluster Science 2003, 14, 299 Reaction Pathways for M = Rh, Ir Journal of Cluster Science 2003, 14, 299 Structural Analysis Black crystals Soluble in toluene, CH2Cl2, and THF IR – when Q = Se, peaks shifted to higher frequencies than for Q = Te Mass spectra – characteristic fragments along with sequential loss of CO units Journal of Cluster Science 2003, 14, 299 CO Flexibility Examined by IR In hexane – group of peaks between 2060 and 1900 cm-1 indicates terminal CO groups One signal for the CO groups in 13C NMR suggests high flexibility in solution In Nujol – peaks below 1900 cm-1 indicate semi-bridging CO groups Confirmed by X-ray diffraction Journal of Cluster Science 2003, 14, 299 X-ray Diffraction Studies Journal of Cluster Science 2003, 14, 299 X-ray Diffraction Studies Journal of Cluster Science 2003, 14, 299 Electrophilic Attack by REX2 Incorporation of group 15 elements E = As, Sb Variations of R-group to create stabilized functionalized clusters [Fe3(μ3-Q)(CO)9]K2 used rather than [Fe3(μ3Q)(CO)9][NEt4]2 to produce pure products Dalton Trans. 2003, 581 J. Organometallic Chem. 2002, 658, 204 Reaction Scheme Dalton Trans. 2003, 581 Structural Analysis X-ray diffraction – nido clusters Square FeEFeQ unit capped by Fe fragment E = As, Sb Q = Se, Te Only 1:1 stoichiometry gives desired product Dalton Trans. 2003, 581 J. Organometallic Chem. 2002, 658, 204 1-D and 2-D Polymers 1-dimensional linear polymer forms immediately in CH3CN Chem. Eur. J. 2005, 11, 2163 Structural Analysis Red crystalline solid Air and light sensitive Very insoluble IR – stretching frequencies indicate terminal CO groups X-ray – small differences in ligand orientation Chem. Eur. J. 2005, 11, 2163 X-ray Diffraction Chem. Eur. J. 2005, 11, 2163 X-ray Diffraction of Polymer Backbone Chem. Eur. J. 2005, 11, 2163 31P MAS-NMR Spectra (X = Cl) Chem. Eur. J. 2005, 11, 2163 31P MAS-NMR Spectra (X = I) Chem. Eur. J. 2005, 11, 2163 31P MAS-NMR Spectral Analysis X = Br, Cl – two multiplets separated by about 150 ppm Homonuclear 1J(31P, 31P) spin-spin interactions Heteronuclear 1J(63/65Cu, 31P) interactions X = I – broad signal Result of differences in orientation of Cp and CO ligands Chem. Eur. J. 2005, 11, 2163 Cp and CO Ligand Orientations Chem. Eur. J. 2005, 11, 2163 Additional Reactions Reactions with CuCl2 and CuBr2 also attempted Red needle-like crystals Yielded same products as CuCl and CuBr Reduction of CuIIX occurs CuIX complexes obviously represent the thermodynamic minimum Chem. Eur. J. 2005, 11, 2163 Preparation of Phosphido Complexes [(RO)3W≡PM(CO)5] R = tBu, 2,4,6-Me2C6H3 M = Cr, W Lone pair of electrons on P coordinated by M(CO)5 to increase stability Thermolysis reaction of [Cp*P{W(CO)5}2] C-H activation followed by loss of CO leads to reactive intermediate [Cp*(CO)2W≡PW(CO)5] Chem. Eur. J. 2001, 7, 1855 Trapping Reactions with Alkynes In situ generation of reactive intermediate and reaction with alkynes Chem. Eur. J. 2001, 7, 1855 Structural Analysis Black (4, 5), yellow (6), and red (7) crystalline solids IR – stretching frequencies of terminal CO groups 31P{1H} NMR and X-ray diffraction studies Chem. Eur. J. 2001, 7, 1855 31P{1H} NMR and X-ray Diffraction of Complex 4 Two singlets correspond to chemically nonequivalent P atoms not coupled through W atom Two 183W satellites per singlet Larger 1J(183W, 31P) value corresponds to bonding of P to W(CO)5 Chem. Eur. J. 2001, 7, 1855 31P{1H} NMR and X-ray Diffraction of Complex 5 Two doublets correspond to chemically nonequivalent P atoms 1 J(31P, 31P) = 407 Hz P-P multiple bond No coupling of P atoms to W atoms Chem. Eur. J. 2001, 7, 1855 31P{1H} NMR and X-ray Diffraction of Complexes 6 and 7 Complex 6 – singlet with two 183W satellites Larger 1J(183W, 31P) value corresponds to bonding of P to W(CO)5 Complex 7 – singlet with one 183W satellite Chem. Eur. J. 2001, 7, 1855 Reaction Pathway Thermolysis of [Cp*P{W(CO)5}2] leads to: Cp* migration C-H activation CO elimination [2+2] cycloadditions with an alkyne Stabilization of the [WPC2] ring - Reaction with W-CO unit (complex 6) - Reaction with 2nd unit of the intermediate (complex 4) Chem. Eur. J. 2001, 7, 1855