Synthesis Of Functional Calix[4]arene Coupling Derivatives And Their Recognition To Metal Ions

With the increase of the national policy on environmental protection and the strengthening of national awareness of environmental protection.The problem of environmental pollution has received widespread attention from the entire society.Calix[4]arene as the third generation supramolecular matrix,Its functionalized products have broad application prospects in the separation and analysis of organic molecules and heavy metal ions.This paper uses calix[4]arene as a structural platform,design and synthesis of calix[4]arene-?-CD and two types of bridged bis-calix[4]arene conjugates,and study the properties of the two types of conjugates.The main work is as follows:1.Ethyl etherification of tetra-tert-butylcalix[4]arene by ethyl acetate and the derivative5,17-dinitro-11,23-di-tert-butyl-25,27-dihydroxy-26.28-diethoxycarbonylmet hoxy calix[4]arene?compound 2?and react with self-made N-?2-aminoethyl?-amino-?-cyclodextrin coupling.Obtained a new conjugate 3 with yield of 40%and a ratio of 1:1 calix[4]arene fragment and ?-cyclodextrin fragment in the molecular structure.The structure of the new conjugate 3 was characterized by 1HNMR,13CNMR,MS?ESI?and FT-TR.The minimum gel concentration and phase transition temperature for the formation of supramolecular gels of conjugate 3 were initially studied.Studies have shown that conjugate 3 can form a gel in DMSO/H2O solvent with a volume ratio of 0.5,the minimum gel concentration is 50 mg·cm-3,and the phase transition temperature is 30?.Adsorption capacity of conjugate 3 to four dyes:MB>BF>RhB>MO.2.The lower edge contains two hydrazide groups,the upper edges are respectively tetra-tert-butyl,tetrahydro and dihydro,dinitrocalix[4]arene derivative compound 4,compound 8 and compound 11 respectively and react with 5,17-Diformyl-11,23-dihydro-26,28-dihydroxy-25,27-di-ethoxycarbonyloxycalix[4]aren e?Compound 10?.Obtained three new bridged bis-calix[4]arene conjugates 5,9 and 12 and their structures were confirmed by 'H NMR,MS?Maldi-tof??ESI?and FT-TR.3.The recognition performance of some metal ions(K+,Ag+,Na+,Mg2+,Ti2+,Ni2+,Zn2+,Pb2+,Co2+,Cd2+,Cu2+,Al³⁺,Fe³⁺,Cr³⁺,La³⁺)by conjugate 5,conjugate 9 and conjugate 12 was preliminary studied.Research indicates:After adding the metal ion solution to the main solution of conjugate 5,the UV absorption intensity decreased,and the maximum absorption intensity of Cd2+,Ag+,Pb2+,Mg2+ decreased by about 50%;After the solution of conjugate 9 was added into the solution of metal ions,the UV absorption intensity decreased,and the UV absorption wavelength of the host solution showed a phenomenon of red shift.The addition of Zn2+,Cd2+,Ni2+,Pb2+,Ag+,and Co2+ decreased the maximum absorption intensity of the host about 30%,the best absorption wavelength red shift 15-20nm.After adding the metal ion solution to the main solution of compound 12,The Cr³⁺ and Ni2+ change the color of the main solution significantly,and the metal ions can be identified by observing the color change.The minimum recognition concentration of Cr³⁺ is 0.16mmol·dm-3,and the minimum recognition concentration of Ni2+ is 0.12mmol·dm-3.4.The UV spectrum studies showed that the minimum recognition concentration of Cr³⁺ for conjugate 12 was 0.023 mmol·dm-3,the minimum recognition concentration for Ni2+ was 0.0070 mmol·dm-3,and the minimum recognition concentration for La³⁺ was 0.092 mmol·dm-1.The inclusion constant of Cr³⁺ is 8321.73dm3·mol-1,the ratio of inclusion is 2:1;The inclusion constant of Ni2+ is 27042.25dm3·mol-1,the ratio of inclusion is 2.4:1;And the inclusion constant of La³⁺is 17672.41dm3·mol-1,the ratio of inclusion is 1:1.The study have shown that the ability of the host conjugate 12 to recognize the above three metal ions is:Ni2+>Cr³⁺>La³⁺.