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 Tungsten- Phosphorous Triple Bond

Fullerene-like Nanoballs [Cp x Fe(η 5 -P 5 )] + Cu I X Cp x = η 5 -C 5 Me 5, η 5 -C 5 Me 4 Et 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: CH 3 CN and CH 2 Cl 2 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:[Cp x Fe(η 5 - P 5 )] x = η 5 -C 5 Me 5 or η 5 -C 5 Me 4 Et Eur. J. Inorg. Chem. 2005, 4023

Structural Analysis Black crystals Broad 31 P 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 D 5h  Ethyl groups attached to Cp decrease symmetry to C s

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 1 st example of electrophilic addition of a Cp*M 2+ unit to an Fe 2 Q face of a cluster M = Rh, Ir Q = S, Se, Te Journal of Cluster Science 2003, 14, 299

Reaction Scheme [Fe 3 (μ 3 -Q)(CO) 9 ][NEt 4 ] 2 + [Cp*M(CH 3 CN) 3 ][CF 3 SO 3 ] 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 Fe 2 Q face Journal of Cluster Science 2003, 14, 299

Addition to the Fe 2 Q Face Two possible reaction pathways  Closo structure with a μ 3 -Q ligand – 60e  Butterfly-shaped structure with a μ 4 -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, CH 2 Cl 2, 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 13 C 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 REX 2 Incorporation of group 15 elements  E = As, Sb Variations of R-group to create stabilized functionalized clusters [Fe 3 (μ 3 -Q)(CO) 9 ]K 2 used rather than [Fe 3 (μ 3 - Q)(CO) 9 ][NEt 4 ] 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, SbQ = 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 CH 3 CN 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

31 P MAS-NMR Spectra (X = Cl) Chem. Eur. J. 2005, 11, 2163

31 P MAS-NMR Spectra (X = I) Chem. Eur. J. 2005, 11, 2163

X = Br, Cl – two multiplets separated by about 150 ppm  Homonuclear 1 J( 31 P, 31 P) spin-spin interactions  Heteronuclear 1 J( 63/65 Cu, 31 P) interactions X = I – broad signal Result of differences in orientation of Cp and CO ligands Chem. Eur. J. 2005, 11, P MAS-NMR Spectral Analysis

Cp and CO Ligand Orientations Chem. Eur. J. 2005, 11, 2163

Additional Reactions Reactions with CuCl 2 and CuBr 2 also attempted Red needle-like crystals Yielded same products as CuCl and CuBr Reduction of Cu II X occurs  Cu I X complexes obviously represent the thermodynamic minimum Chem. Eur. J. 2005, 11, 2163

Preparation of Phosphido Complexes [(RO) 3 W≡P  M(CO) 5 ] R = tBu, 2,4,6-Me 2 C 6 H 3 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) 2 W≡P  W(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 31 P{ 1 H} NMR and X-ray diffraction studies Chem. Eur. J. 2001, 7, 1855

31 P{ 1 H} NMR and X-ray Diffraction of Complex 4 Two singlets correspond to chemically non- equivalent P atoms not coupled through W atom Two 183 W satellites per singlet  Larger 1 J( 183 W, 31 P) value corresponds to bonding of P to W(CO) 5 Chem. Eur. J. 2001, 7, 1855

Two doublets correspond to chemically non- equivalent P atoms  1 J( 31 P, 31 P) = 407 Hz  P-P multiple bond No coupling of P atoms to W atoms Chem. Eur. J. 2001, 7, P{ 1 H} NMR and X-ray Diffraction of Complex 5

Complex 6 – singlet with two 183 W satellites  Larger 1 J( 183 W, 31 P) value corresponds to bonding of P to W(CO) 5 Complex 7 – singlet with one 183 W satellite Chem. Eur. J. 2001, 7, P{ 1 H} NMR and X-ray Diffraction of Complexes 6 and 7

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 [WPC 2 ] ring - Reaction with W-CO unit (complex 6) - Reaction with 2 nd unit of the intermediate (complex 4) Chem. Eur. J. 2001, 7, 1855