سنتز و شناسايي كمپلكس هاي ارتوپالاديتa - كتوفسفرايليدهاي پايدار (BrBPPY) ,(NO2BPPY),(PhBPPY) درموقعيت اندوباليگاندهاي دو دندانه اي فنانترولين بي پيريدين، 1و2- بيس دي فنيل فسفينواتان و 1و 3- بيس دي فنيل فسفينوپروپان

چكيده انگليسي :

Synthesis and Characterization of Stabilized Orthopalladated Complexes Keto Phosphorus Ylides PhBPPY NO2BPPY and BrBPPY in Endo Position with Bidentate ligands Phenanthroline Bipyridine 1 2 Bis diphenylphosphino ethane 1 3 Bis diphenylphosphino propane Farzaneh Borzooie f borzooei@ch iut ac ir Date of Submission 2010 6 23 Department of Chemistry Isfahan University of Technology Isfahan 84156 83111 Iran Degree M Sc Language Farsi Supervisor Kazem Karami Karmi@cc iut ac ir Abstract In this thesis phosphorus ylides PhBPPY NO2BPPY and BrBPPY have been synthesized through the formation of phosphonium salt and dihydrogenation followed by the reaction of Pd OAc 2 and the orthopalladated dinuclear complexes Pd Cl PhBPPY 2 Pd Cl NO2BPPY 2 and Pd Cl BrBPPY 2 have been produced The reaction of dinuclear complexes and bidentate ligands L bipy 2 2 bipyridine phen phenanthroline dppe bis diphenylphosphino ethane dppp bis diphenylphosphino propane giving the stabilized mononuclear orthopalladated complexes Pd phen XBPPY Pd bipy XBPPY Pd dppe XBPPY and Pd dppp XBPPY X Ph NO2 Br in endo position The complexes were chractrized by FT IR NMR CHN conductivity and X ray diffraction study of Pd phen BrBPPY Pd bipy BrBPPY Pd dppe NO2BPPY The @ CO band which is sensitive to complexation occurs from 1505 to 1515 cm 1 in the parent ylides These bands appear at lower energies compared to that found in the phosphonium salts due to the charge delocalization present in such compounds Coordination of ylide through the carbon atom causes an increase in the @ CO band whereas for O coordination a lowering of the @ CO band is expected The IR spectra of all complexes show a strong absorption in the range of 1620 1630 cm 1 which have been shifted to higher frequency with respect to the parent ylides meaning that the ylides are C bonded to the palladium center The @ P C band frequencies occur at 881 860 and 883 cm 1 in the parent ylides PhBPPY NO2BPPY and BrBPPY respectively and are shifted to lower frequencies for the complexes suggesting some removal of the electron density of the P C bonds The 1H NMR signals for the PCH group of complexes are shifted downfiled compared to that of the free ylides as a consequence of the inductive effect of the metal center In the 1H NMR spectra for dinuclear complexes the signals due to the methinic proton were broad minor or broad doublets major The presence of two lines of different intensity on each spectrum can be originated from the presence of two diasteroisomers RR SS and RS SR as a result of the C bonding of the ylide and the dinuclear nature of Pd Cl PhBPPY 2 Pd Cl NO2BPPY 2 and Pd Cl BrBPPY 2 In the 31P 1H NMR spectra of all complexes the presence of one signal group confirm a single isomer for each complexes The 31P NMR spectra of the bidentate diphosphine have one signal while the 31P NMR spectra of Pd II complexes with a bidentate diphosphine show two signal due to different trans effect of arylic and ylidic carbons The results of conductivity show that the molar activity of orthopalladated complexes are within the range for 1 1 electrolytes which demonstrate the existence of the TfO as counter ion in the solution Single crystals of Pd phen C6H4 PPh2CH C O C6H4 Br E C C 2 Pd bipy C6H4 PPh2CH C O C6H4 Br E C C 2 and Pd dppe C6H4 PPh2CH C O C6H4 NO2 E C C 2 suitable for X ray crystallography were obtained The palladium atoms of complexes are located in disorted square planer environments In complexe Pd dppe C6H4 PPh2CH C O C6H4 NO2 E C C 2 the Pd P 2 bond length is shorter than Pd P 3 due to different trans effect of arylic and ylidic carbons The ORTEP diagram of the complexes demonstrate the orthopalladation occuring at the Ph rings of the phosphine unit in endo position In the crystal structure of complexes cations anions and solvent molecules are linked into a network by intra intermolecular hydrogen bonds Keyword Phosphorus ylides Palladium II complexes Orthopaladation Bidentate ligandes

برزوئي، فرزانه

كمپلكس هاي پالاديم ﴿II﴾ , ارتوپالاديم دارشدن