5848

5463

كارشناسي ارشد

شيمي آلي

اصفهان: دانشگاه صنعتي اصفهان، دانشكده شيمي

1389

چهارده،92ص.: مصور،جدول،نمودار

ص.ع.به فارسي و انگليسي

مهران غياثي

شادپور ملك پور

10/2/90

كاظم كرمي، محمد قريشي

شيمي

ID5463

به فارسي و انگليسي: قابل رويت در نسخه ديجيتالي

Synthesis and characterization of Palladium Nano Catalysts immobilized on silica via two new ligands and their application in the Suzuki and Sonogashira reactions Monireh Zarghani m zarghany@ch iut ac ir November 2 2011 Department of Chemistry Isfahan University of Technology Isfahan 84156 83111 Iran Degree M Sc Language Farsi Supervisor Mehran Ghiaci mghiaci@cc iut ac ir Abstract In this project two new ligands with different features and properties have bean grafted on the surface of silica for immobilization of palladium nano particles The synthesised catalysts were applied for Suzuki Miyaura and Sonogashira reactions This project was conducted in two parts In the first step silica was modified by 3 aminopropyltrimethoxysilane and cyanuric chloride In the part one of the work N Heterocyclic Carbene was used as the ligand To prepared the carbene ligand an ionic liquid was synthesized and then it was linked to the surface of modified silica Eventually synthesized palladium nano catalyst was prepared from the modified silica and palladium acetate In second part of the work L Cysteine amino acid as ligand was used and linked to surface of the modified silica Then similar to part one palladium nano catalysis was coordinated with to the carrier ligand Different techniques such as FT IR CHNS BET SEM ICP and TEM were used for characterization of the catalysts The catalytic performance was examined in the Suzuki and Sonogashira reactions The products were analyzed by GC and GC MS Furthermore the reaction conditions were optimized for the reactions The catalysts showed excellent activity towards Suzuki and Sonogashira coupling In Suzuki reaction phenylbronicacid was reacted with some aryl halids such as iodobenzene bromobenzene 4 bromonitrobenzene 3 bromoanisole chlorobenzene in 120 C for 12 h Water and K2CO3 were used as solvent and base respectively The conversion was over 98 for iodobenzene for two catalysts The catalysts were also effective for Sonogashira coupling In Sonogashira reaction iodobenzene reacted with phenylacetylene in 80 C for 24 h DMF H2O 3 1 and NaOAc were used as solvent and base respectively The reusability of the catalysts were tested in the two reactions The presence of the silica support makes the nano particles resistant to aggregation and precipitation and also helps preserve their catalytic activity during the five cycles The nano catalysts can be easily recovered and repeatedly reused without loss of activity Keywords Palladium N Heterocyclic Carbene L Cysteine Suzuki reaction Sonogashira reaction

مهران غياثي

شادپور ملك پور

كاظم كرمي، محمد قريشي