Modification Of Cyclodextrin And Its Application In Catalyzing Carbon-Carbon Coupling Reaction

β-cyclodextrin（β-CD）is a natural cyclic macromolecular compound and has been widely used in organic synthesis reactions,especially in the field of metal-catalyzed organic synthesis reaction which has shown excellent catalytic activity.The Suzuki coupling reaction and Heck coupling reaction catalyzed by transition metal palladium are the most important methods for the construction of C-C bonds.At present,with the continuous development of green chemistry,researchers are committed to using green solvents such as water as reaction media to conduct catalytic research,and have achieved remarkable results.The following contents were mainly included in this thesis:1.The synthesis and characterization ofβ-CD derivativesTaking mono-（6-O-p-toluenesulfonyl）-β-CD（mono-（6-OTs）-β-CD）as important intermediate,mono-（6-L-serine-6-deoxy）-β-CD,mono-（6-L-threonine-6-deoxy）-β-CD,mono-（6-L-tyrosine-6-deoxy）-β-CD,mono-（6-guanosine-6-deoxy）-β-CD were synthesized via nucleophilic substitution reaction with L-serine,L-threonine,L-tyrosine and guanosine respectively.In addition,usingβ-CD and chlorosulfonic acid as raw materials,sulfonatedβ-CD with different degrees of substitution were synthesized through sulfonation reaction.The structures ofβ-CD derivatives were analyzed and characterized by using UV,FT-IR,¹H NMR,¹³C NMR and ESI-MS.2.Amino acid modifiedβ-CD/Pd biomimetic catalyzed Suzuki coupling reaction in aqueous phaseUsing mono-（6-L-serine-6-deoxy）-β-CD,mono-（6-L-threonine-6-deoxy）-β-CD,and mono-（6-L-tyrosine-6-deoxy）-β-CD as ligands,palladium acetate as the palladium source,and the in-situ generated catalytic systems were used biomimetic catalysis of Suzuki coupling reaction in aqueous phase.The results showed by using K₃PO₄·7H₂O as the acid scavenger,p-bromotoluene and phenylboronic acid as substrates,the coupling yields can be up to 83%,88%and 94%respectively with 0.01 mol%of the catalyst loading at 80°C for 2 h.For brominated aromatic hydrocarbons and arylboronic acids with different substituents,the steric hindrance of the substrate has little effect on the yield and the electronic effect of the substrate have a certain effect on the yield,the catalytic reaction yields can reach 73%-97%.The ligands of amino acid modifiedβ-CD have high catalytic activity and stability,mild experimental conditions,recyclable catalysis,and environmentally friendly reaction medium.In addition,Suzuki reaction was performed using synthesized mono-（6-guanosine-6-deoxy）-β-CD as a ligand,and the yield was 96%.3.Suzuki coupling reaction catalyzed by sulfonatedβ-CD/Pd in water-DMF phaseBy adopting sulfonatedβ-CD（S₁-β-CD and S₂-β-CD）with substitution degree of0.15 and 1.21 as ligands,palladium acetate as the palladium source,and DMF phase in-situ generated catalytic systems for organic-water phase catalyzed Suzuki coupling reaction.The results showed by using K₃PO₄·7H₂O as the acid scavenger,p-bromotoluene and phenylboronic acid are used as substrates,and the solvent volume ratio is DMF/H₂O=1/19,the coupling yields can reach 76%and 96%respectively with0.0034 mol%of the catalyst loading at 80°C for 2 h.For brominated aromatic hydrocarbons and arylboronic acids with different substituents,the steric hindrance and electronic effect of the substrate have a certain effect on the yield,and the electronic effect is higher than the effect of the steric on the yield.The sulfonatedβ-CD was obtained in a simple and novel for catalyzing the Suzuki coupling reaction.S-β-CD/Pd（OAc）₂ is a catalyst complex with high activity,high stability and low palladium usage.It can efficiently catalyze the reaction under mild conditions and without phase transfer agent.4.Mono-（6-m-aminobenzoic acid-6-deoxy）-β-CD/Pd catalyzed Heck coupling reaction in aqueous phaseBy adopting mono-（6-m-aminoaminobenzoic acid-6-deoxy）-β-CD as ligand,palladium acetate as the palladium source,and the in-situ generated catalytic systems were used to catalyze Heck coupling reaction in aqueous phase.The experiment showed that when iodobenzene and ethyl acrylate were used as substrates,K₂CO₃（0.5mmol）as the acid scavenger,with 0.20 mol%of the catalyst loading,the reaction was performed at 150°C for 12 h,and the coupling yield was 91%.A variety of aryl iodides can efficiently catalyze Heck coupling reaction with alkenyl compounds such as acrylates in water phase,with high conversion and yield.The catalytic system provides a good route for the synthesis of cinnamate derivatives and other pharmaceutical intermediates.At the same time,it has the characteristics of environmental friendliness,simple post-treatment and high reaction efficiency,and has certain application prospects.