5055

4752

كارشناسي ارشد

شيمي معدني

اصفهان: دانشگاه صنعتي اصفهان، دانشكده شيمي

1388

ده، 127ص: مصور، جدول، نمودار

ص.ع.به: فارسي و انگليسي

كاظم كرمي

5/12/88

مهدي امير نصر، شهرام تنگستاني نژاد

شيمي

ID4752

به فارسي و انگليسي: قابل رويت در نسخه ديجيتال

Synthesis and Characterization of mono and dinuclear Orthopalladated Hg II and Ag I complexes with 4 Phenyl benzuyl methylene three phenyle Phosphoran PhBPPY by IR NMR and X ray spectroscopy Hamid Dalvand Hamiddalvand57@yahoo com 20 12 2009 Department of Chemistry Isfahan University of Technology Isfahan 84156 83111 IranDegree M Sc Language FarsiKazeme KaramiAbstract The ortho metalated complex Pd Cl C C C6H4 PPh2CHC O C6H4 Ph 4 2 2 can beprepared by refluxing equimolecular amounts of Pd OAc 2 and Ph 3PCHCOC6H4 Ph 4 1 PhBPPY in MeOH and CH2Cl2 for 24 h followed by addition of excess NaCl Complex 2 reactswith 4 MePy to give the mononuclear derivative PdCl PhC6H4COCHPPh2C6H4 4 MePy 5 whosecrystal structure has been determined by X ray diffraction The precursor of Pd Cl C C C6H4 PPh2CHC O C6H4Ph 4 2 2 could not be isolated in a pure form but it can be used as thestarting material for the synthesis of derivatives of mono nuclear cyclo palladated complexes The C C metalated chelate is very stable as shown by the reactions of 2 with PPh3 3 MePy 4 MePy and 2 4 6 Me3Py Orthometallation and ylide C coordination in complexes 3 6 are characterized withelemental analysis as well as various spectroscopic techniques The IR spectrum of 1 shows a strongabsorption at 1507cm 1 due to the carbonyl stretch frequency The absorption due to the carbonylstretch frequency clearly appears at lower energies than expected about 1720 cm 1 due to theconjugation of the C O bond with the P C bond 31P 1H NMR spectra shows a single peak at about17 2 ppm a position shifted to low filed with respect to that observed in other non stabilized systems about 0 6 ppm and showing the lower shielding of the P atom in the stabilized compounds due todelocalization The IR spectra of 2 6 shows a sharp very strong absorption in the 1618 1625 cm 1range The observation of this positive shift value for vCO the complexes indicates that ylide be C coordinated to Pd II In the 1HNMR spectra for 2 the signals due to the methinic proton were broad minor or broad doublet major The 31P 1H NMR spectrums of 2 showed single broad peak at18 41 ppm for both isomer The bridge splitting reactions of 2 with neutral ligands producedexclusively the corresponding mononuclear compounds 3 6 1HNMR and 31P 1H NMR signals forthe PCH group of all complexes were shifted to downfield in comparison with those in free ylides as aconsequence of the inductive effects of the metal center The 1HNMR spectra complex 4 and 5 showed two signal for the CH group that must be arisen from a fast equilibrium between the cis andtrans isomers or reasons that show a dynamic activity for exchange of Methyl Py and Cl groups insolution The 1HNMR spectra complex 6 showed one signal for the CH group at 5 27 ppm The 31P 1 H NMR spectra show only one sharp singlet at 18 92 ppm in the complexes 6 The reactions of thetitle ylides with HgX2 X Cl Br I in equimolar ratios using dry MeOH as solvent have yielded Hg2 Cl 4 PhBPPY 2 7 Hg2 Br 4 PhBPPY 2 8 and Hg2 I 4 PhBPPY 2 9 and respectively The reactions of the title ylides with AgTfO and AgBF4 in molar ratios 2 1 using dry MeOH assolvent have yielded Ag PhBPPY 2 TfO 10 and Ag PhBPPY 2 BF4 11 The analytical data IRand 1H and 31P 1H NMR data of the products were obtained Keywords Cyclopalladated C C metalate chelate Orthometallation dynamic

كاظم كرمي

مهدي امير نصر، شهرام تنگستاني نژاد