كاربرد كمپلكس آلي فلزي پالاديم با ساختارهاي ديمر و مونومر در سنتز و شناسايي محصول واكنش هاي سونوگاشيرا و سوزوكي

چكيده انگليسي :

Application of Organometallic Compound with Dimer and Monomer Structure in the Sonogashira and Suzuki Reactions Hannaneh Rahimi Desperado iut@yahoo com January 27 2012 Department of Chemistry Isfahan University of Technology 84156 83111 Isfahan IranDegree M Sc Language FarsiProf A R Hajipour Email haji@cc iut ac irAbstract The vast application of carbon carbon bond formation reactions in different areas including synthesis of complexcompounds from simpler reactants are of great importance According to this fact in recent years these reactionhave become versatile tools in organic chemistry It should be mentioned that Sonogashira and Suzuki cross coupling reactions are of the most efficient methods The Sonogashira cross coupling reactions acetylenes with arylor alkenyl halides or triflates have been developed in organic chemistry and material science for the production ofinternal alkynes and enynes Alkynes are as the building block of a wide range of pharmaceuticals natural products biological active molecules conducting polymers non linear optical and liquid crystal materials The palladium catalyzed cross coupling of nucleophilic organborans with electrophilic organic halides and triflates known as theSuzuki cross coupling reaction has emerged as a powerful and versatile tool for the synthetis of substituted biaryls Biaryls are applied as the building block of a wide range of herbicides pharmaceuticals natural and bioactiveproducts microelectrode arrays conducting polymers and liquid crystal materials Palladium salts or a complex ofthis metal are the most applied catalysts for these reactions One of the important types of these complexes arePalladacycles Palladacycles can be defined as heterocyclic compounds that one of their heteroatoms in theirstructures is palladium Palladacycles application as active intermediates was noticed in organic synthesis whenthey were discovered in 1960s In continuation their application in carbon carbon bonds formation as homogeneouscatalysts became important In the recent years these compounds have found variable applications in the synthesisof organic compounds and formation of new C C bonds as catalyst Herein application of monomeric and dimeric palladacycle complex of Homoveratrylamine as a pre catalyst isstudied in carbon carbon bond formation under conventional heating conditions in an oil bath First the activity of dimeric complex Homoveratrylamine Pd C6H2 CH2CH2NH2 OMe 2 3 4 Br 2 3 wasstudied in the Sonogashira cross coupling reaction The catalyst has great activity in this reaction The yields werevery good to excellent under optimized conditions of using piperidine as base N Methyl 2 pyrrolidone as solvent at100 C temperature This catalytic system promoted the desired coupling products in moderate to excellent yieldsand short reaction times As the second part of our project the difference between catalytic application of dimeric Pd C6H2 CH2CH2NH2 OMe 2 3 4 Br 2 3 and monomeric Pd C6H2 CH2CH2NH2 OMe 2 3 4 Br PPh3 3a were studied inSuzuki Miyaura cross coupling reaction of aryl halides using phenyl boronic acid under similar conditions ofSonogashira cross coupling reaction Results showed that monomeric Palladacycle has more efficiency Thus theSuzuki Miyaura cross coupling reaction of various aryl halides with monomeric complex was performed in ethanolas a green solvent and in the presence of K2CO3 as base at 60 C temperature The monomeric palladacycle wasapplied in the synthesis of biphenyls from aryl chlorides which are cheaper and more available The appliedmonomeric complex was oxygen resistant so all reactions were performed under air atmosphere Again The resulted yields in this case were very good to excellent and the reaction times were reduced Theproducts were characterized by comparing their m p IR 1H NMR 13C NMR spectra with those found in theliterature Keywords Palladacycle Homogeneous Pharmaceuticals Herbicides N Methyl 2 pyrrolidone Sonogashira reaction Suzukireaction

رحيمي، حنانه

كاربرد كمپلكس آلي فلزي پالاديم با ساختارهاي ديمر و مونومر در سنتز و شناسايي محصول واكنش هاي سونوگاشيرا و سوزوكي

پالاداسيكل , هتروسيكل , N-متيل-2-پيروليدون , كاتاليزور