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10 th European Workshop on Phosphorus Chemistry. Oxidatively induced P-C and P-O bond formation through reductive coupling between phosphanido and N^C, N^O or O^O ligands Stefano TODISCO , a Piero MASTRORILLI, a Mario LATRONICO, a Vito GALLO, a Andersson ARIAS, b Juan FORNIÉS, b
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10thEuropean Workshop on PhosphorusChemistry • Oxidatively induced P-C and P-O bond formation • through reductive coupling between • phosphanido and N^C, N^O or O^O ligands • Stefano TODISCO,a Piero MASTRORILLI,a Mario LATRONICO,a • Vito GALLO,a Andersson ARIAS, b Juan FORNIÉS,b • Consuelo FORTUNO,b Antonio MARTIN,b • aDicatech, Politecnico di Bari and istituto CNR-ICCOM, • Via Orabona 4 CAMPUS, I-70125 Bari, ITALY • b Departamento de Química Inorgánica, Instituto de SíntesisQuímica y CatálisisHomogénea, Universidad de Zaragoza E-50009Zaragoza SPAIN Regensgurg, Germany, March 18th-21th 2013
Bridging phosphido diplatinum complexes Diorganophosphido bridges are used as flexible ligands able to endow clusters and dimetallic complexes with reduced fragmentation.
Coupling of two bridging phosphido ligand Reversible Transformation of Two Diphenylphosphanido Ligands into the Neutral Tetraphenyldiphosphane Ligand 44 VEC J.Forniès, C. Fortuno, S. Ibanez, A. Martin, A. C. Tsipis, and C. A. Tisipis,Angew. Chem. Int. Ed., 2005, 44, 2407- 2410
“Reactive” Bridging Phosphides Reversible intramolecular reductive coupling of a bridging Phosphido ligand and a C6F5 group I. Ara, N. Chaouche, J. Forniès, C. Fortuno, A. Kribii, A. C. Tsipis,Organometallics, 2004, 23, 1797- 1810
“Reactive” Bridging Phosphides I. Ara, J. Forniès, C. Fortuno, S. Ibanez, A. Martin,Inorg. Chem., 2008, 47, 9069-9080 I. Ara, N. Chaouche, J. Forniès, C. Fortuno, A. Kribii, A. C. Tsipis,Organometallics, 2006, 25, 1084-1091
Bridging phosphanido diplatinum complexes Are couplings involving bridging phosphides limited to C6F5?
Our study Hydroxyquinolinate Benzoquinolinate Picolinate Acac Oxidation with I2
Synthesis of complexes 2-3-4 ** Forniés, J.; Fortuno, C.; Navarro, R.; Martinéz, F.; Welch, A. J.; J. Orgamet. Chem., 1990, 394, 643-658 * Alonso, E.; Fornies, J.; Fortuno, C.; Martin, A.; Guy Orpen, A.; Organometallics, 2003, 22, 5011-5019
The reaction of complex1 in dichloromethane Pt(1) – Pt(2) = 3.255 Å Pt(1)-P(1)-Pt(2) = 90.95° Pt(1)-I-Pt(2) = 74.88° P(1)-Pt(1)-I = 82.25° P(1)-Pt(2)-I = 82.57°
The reaction of complex1 in dichloromethane Monitoring reaction by NMR we detected the species 5*
The reaction of complex1 in acetone First Mixed Valence Diphosphido Pt(II)Pt(IV) system
Crystal structure of 5* Pt(1) – Pt(2) = 3.572 Å DiscardanyPt···Ptinteraction Pt(1)-P(1)-Pt(2) = 100.53° Pt(1)-P(2)-Pt(2) = 99.38° P(1)-Pt(1)-P(2) = 79.38° P(1)-Pt(2)-P(2) = 76.93°
NMR characterization 1H COSY 1H NOESY 1H-31P HMQC 1H-195Pt HMQC
31P {1H} NMR Acetone-d6 Complex 1 Complex 5*
195Pt {1H} NMR Acetone-d6 Complex 1 - 3717 ppm Pt2 Pt1 Complex 5* - 2917 ppm Pt2 ≈ Pt1
Spectroscopic properties of 5*:1H-31P HMQC Acetone-d6, 298K o-B o-D o-C o-A
1H EXSY Acetone-d6, 298K tm = 600 ms p-A p-B o-B o-A m-A D C Exchange between phenyls rings
Proposed dynamic process The process presumably involves species with bridging phosphane ligand
Examples of bridging phosphanes Although tertiary phosphanes act almost exclusively as terminal ligand, bridging phosphane ligand have appeared sporadically in the literature. Réau (1) Pechmann (2) Leoni (3) (1)Chem. Eur. J. 2008, 14, 3391- 3403 (2)Dalton Trans. 2004, 959 - 966 (3)Inorg. Chem. 1991, 30, 4690 - 4692
A Dissociative Mechanism Complex 5* CD2Cl2 5 eq I- After 3 days 31P-NMR didn’t show conversioninto 5 Complex 5* CD2Cl2 After 3 days 31P-NMR showed a conversion of 25% into 5
Reactions of N^O and O^O complexes Hydroxoquinolinate Picolinate Acac Oxidation with I2
Reactions of N^O and O^O complexes Complex 6 Complex 8
Monitoring reactions in acetone by 195Pt NMR - 2385 ppm - 2501 ppm - 2024 ppm
(-) HR-ESIMS of complexes 6*-7*-8* in acetonitrile Meas. Meas. Meas. Calc. Calc. Calc.
Thanks for your attention!