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Manfred Scheer Coordination Chemistry of Phosphorous Containing Compounds Angela Dann May 8, 2006

Manfred Scheer Coordination Chemistry of Phosphorous Containing Compounds

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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 - PowerPoint PPT Presentation

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Page 1: Manfred Scheer Coordination Chemistry of Phosphorous   Containing Compounds

Manfred ScheerCoordination Chemistry of Phosphorous Containing Compounds

Angela Dann

May 8, 2006

Page 2: Manfred Scheer Coordination Chemistry of Phosphorous   Containing Compounds

Research Interests

Supramolecular Arrays

Fullerene-like nanoballs Heteronuclear clusters with main group

metal incorporation

1-Dimensional and 2-Dimensional Polymers

Complexes Containing a Tungsten-Phosphorous Triple Bond

Page 3: Manfred Scheer Coordination Chemistry of Phosphorous   Containing Compounds

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

Page 4: Manfred Scheer Coordination Chemistry of Phosphorous   Containing Compounds

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(η5-P5)] x = η5-C5Me5 or η5-C5Me4Et

Eur. J. Inorg. Chem. 2005, 4023

Page 5: Manfred Scheer Coordination Chemistry of Phosphorous   Containing Compounds

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

Page 6: Manfred Scheer Coordination Chemistry of Phosphorous   Containing Compounds

X-ray Structure

Eur. J. Inorg. Chem. 2005, 4023

Page 7: Manfred Scheer Coordination Chemistry of Phosphorous   Containing Compounds

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

Page 8: Manfred Scheer Coordination Chemistry of Phosphorous   Containing Compounds

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

Page 9: Manfred Scheer Coordination Chemistry of Phosphorous   Containing Compounds

Initial Attempts Attachment at edge or corner rather than at

the Fe2Q face

Journal of Cluster Science 2003, 14, 299

Page 10: Manfred Scheer Coordination Chemistry of Phosphorous   Containing Compounds

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

Page 11: Manfred Scheer Coordination Chemistry of Phosphorous   Containing Compounds

Reaction Pathways for M = Rh, Ir

Journal of Cluster Science 2003, 14, 299

Page 12: Manfred Scheer Coordination Chemistry of Phosphorous   Containing Compounds

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

Page 13: Manfred Scheer Coordination Chemistry of Phosphorous   Containing Compounds

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

Page 14: Manfred Scheer Coordination Chemistry of Phosphorous   Containing Compounds

X-ray Diffraction Studies

Journal of Cluster Science 2003, 14, 299

Page 15: Manfred Scheer Coordination Chemistry of Phosphorous   Containing Compounds

X-ray Diffraction Studies

Journal of Cluster Science 2003, 14, 299

Page 16: Manfred Scheer Coordination Chemistry of Phosphorous   Containing Compounds

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(μ3-Q)(CO)9][NEt4]2 to produce pure products

Dalton Trans. 2003, 581J. Organometallic Chem. 2002, 658, 204

Page 17: Manfred Scheer Coordination Chemistry of Phosphorous   Containing Compounds

Reaction Scheme

Dalton Trans. 2003, 581

Page 18: Manfred Scheer Coordination Chemistry of Phosphorous   Containing Compounds

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, 581J. Organometallic Chem. 2002, 658, 204

Page 19: Manfred Scheer Coordination Chemistry of Phosphorous   Containing Compounds

1-D and 2-D Polymers

1-dimensional linear polymer forms immediately in CH3CN

Chem. Eur. J. 2005, 11, 2163

Page 20: Manfred Scheer Coordination Chemistry of Phosphorous   Containing Compounds

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

Page 21: Manfred Scheer Coordination Chemistry of Phosphorous   Containing Compounds

X-ray Diffraction

Chem. Eur. J. 2005, 11, 2163

Page 22: Manfred Scheer Coordination Chemistry of Phosphorous   Containing Compounds

X-ray Diffraction of Polymer Backbone

Chem. Eur. J. 2005, 11, 2163

Page 23: Manfred Scheer Coordination Chemistry of Phosphorous   Containing Compounds

31P MAS-NMR Spectra (X = Cl)

Chem. Eur. J. 2005, 11, 2163

Page 24: Manfred Scheer Coordination Chemistry of Phosphorous   Containing Compounds

31P MAS-NMR Spectra (X = I)

Chem. Eur. J. 2005, 11, 2163

Page 25: Manfred Scheer Coordination Chemistry of Phosphorous   Containing Compounds

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

31P MAS-NMR Spectral Analysis

Page 26: Manfred Scheer Coordination Chemistry of Phosphorous   Containing Compounds

Cp and CO Ligand Orientations

Chem. Eur. J. 2005, 11, 2163

Page 27: Manfred Scheer Coordination Chemistry of Phosphorous   Containing Compounds

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

Page 28: Manfred Scheer Coordination Chemistry of Phosphorous   Containing Compounds

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

Page 29: Manfred Scheer Coordination Chemistry of Phosphorous   Containing Compounds

Trapping Reactions with Alkynes In situ generation of reactive intermediate

and reaction with alkynes

Chem. Eur. J. 2001, 7, 1855

Page 30: Manfred Scheer Coordination Chemistry of Phosphorous   Containing Compounds

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

Page 31: Manfred Scheer Coordination Chemistry of Phosphorous   Containing Compounds

31P{1H} NMR and X-ray Diffraction of Complex 4 Two singlets correspond to chemically non-

equivalent 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

Page 32: Manfred Scheer Coordination Chemistry of Phosphorous   Containing Compounds

Two doublets correspond to chemically non-equivalent P atoms 1J(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 Complex 5

Page 33: Manfred Scheer Coordination Chemistry of Phosphorous   Containing Compounds

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

31P{1H} NMR and X-ray Diffraction of Complexes 6 and 7

Page 34: Manfred Scheer Coordination Chemistry of Phosphorous   Containing Compounds

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