Preparationand Catalytic Coupling Reactions In C-C Bond Building Of Novelligands With Nitrogen And Phosphorus And Their Pd Complexes

In recent years, with the sustainable development strategy being carried out,the environment friendly "Green Chemistry" has become an irresistible trend ofchemistry development. The formations of carbon-carbon bonds are always anorganic chemistry domain research hot spot. The coupling reaction betweenPHAHs and nucleophilic reagents can be efficiently catalyzed by transition metalcatalysts or the complexes,it is becoming more and more important for scientists todesign and synthesis novel ligands for transition metal catalysts in the couplingreactions.In this paper, two new types of ligands were prepared taking2-bromobenzaldas the raw material:One is a bidentate ligand containing N, P atoms, the other is thewater-soluble sulfonate containing phosphorus ligands. Then the catalyticproperties of their palladium complexes were observes carefully. The maincontents in this paper are as follows:(1) Preparation of the N, P-bidentate palladium complexes and theirapplication in Suzuki reactionN1-(2-diphenyl p-toluenesulfonic)-naphthalene1,8-ammonia ligand and2-(diphenyl phosphate-benzyl)-pyridine-3-amine ligand were prepared and theirstructures were characterized by1H,13C and31P NMR, High-resolution MS, and IRspectrum. The crystal structures of these two ligands were obtained and confirmedby X-ray single crystal diffraction analysis. The corresponding palladiumcomplexes were obtained by coordinated with potassium tetra-chloropalladate atroom temperature.The catalytic properties of the complexes were investigated inthe Suzuki coupling reaction and the reaction parameters were optimized. Theresults show that: KOH as the alkali agent, absolute ethyl alcohol as the solvent,the whole process is taken place in the microwave reaction kettle, WB-GSH forshort, and at a constant temperature of120℃for10min and only0.01mol catalyst can effectively catalyze the Suzuki cross-coupling reaction of phenylboronic acidor4-methoxyphenylboronic acid with bromobenzene with a good yield rangingfrom72.8%to99.9%. even for the chlorobenzene which is with a lower activity,the yield can be97.0%.(2) Preparation3-(2-diphenyl phosphine)-benzyl oxygen radicals-propane-1-sodium sulfonate ligand. and its catalytic property in the coupling reactions.The3-(2-diphenyl phosphine)-benzyl oxygen-radicals-propane-1-sodiumsulfonate ligand was synthesized by using2-bromobenzald as the initial materialthrough two steps reaction. And the structures of ligand and the complex werecharacterized by NMR, MS,31PNMR and IR. Then its palladium complexes wasobtained by coordinating with potassium tetra-chloropalladate. Its catalyticbehavior in coupling reaction with microwave heating in alkali condition wasobserved. The coupling biphenyl product was purified by means of columnchromatography was characterized by1HNMR. What is more, the effect of solventand base on catalytic activity was studied. The results shows that: the optimalconditions of reaction are at temperature of120℃, DMF/H2O as solvent bymeans of microwave reaction for10min. And the yield of the product above is99.0%. The repetition of catalyst shows that the yield of the product is68.4%afterfive times.(3) Preparation of the resveratrol similar compoundThe complex of3-(2-diphenyl phosphine)-benzyl oxygen radicals-propane-1-sodium sulfonate-palladium (Ⅱ) was applied to catalyze the syntheticreaction of the resveratrol similar compound. The compound was synthesized bymeans of using β-bromine styrene,1-bromine-(3,4-dimethoxy benzene) ethyleneor1-bromine-(3,5-dimethoxy benzene) ethylene as the raw material which reactedwith phenylboronic acid, p-methoxyphenylboronic acid and3-thienylboronic acid,respectively. And the potassium hydroxide was added into reactions as the alkali.The resveratrol similar compounds were obtained with a microwave heating to thetemperature of120℃for10min. The products were characterized by1H NMR, IR.