Synthesis And Molecular Recognition Base On Pyridine Diamine Compounds

Macrocyclic compounds are a class of substances with special structures and are hotspots in the field of supramolecular chemistry.Functionalized macrocycles have broad application prospects in the fields of biology,medicine,materials,and catalysis.Designing and synthesizing new macrocyclic compounds is one of the driving forces to make great progress in supramolecular field.However,the special structure of macrocyclic compounds makes their synthesis still a great challenge.In addition,designing and synthesizing artificial receptors and realizing selective recognition of specific ions by simple analytical means have always been important research contents in the field of environment and life sciences.To this end,we designed and synthesized chiral Schiff base macrocyclic compounds,chiral aromatic diimide macrocyclic compounds and artificial probes that can specifically recognize nitrate based on pyridinium diamine.The specific research content includes the following three aspects:One is the synthesis of a chiral Schiff base macrocyclic compound.The 2,6-diacetylpyridine was used as a raw material,and the ketone was reduced to a chiral alcohol by a chiral boron reagent.The chiral alcohol then changed into chiral pyridinium diamine with configuration flip by Mitsunobu reaction.Finally,a chiral Schiff base macrocyclic compound of"2+2"type is obtained by condensation of a chiral pyridine diamine with a dialdehyde.The structure was characterized by nuclear magnetic resonance,mass spectrometry,circular dichroism and single crystal diffraction.The second is the synthesis of chiral aromatic diimide macrocyclic compounds.The chiral pyridinediamine is condensed with an aromatic dianhydride compound to obtain a chiral phthalic anhydride diimide and a naphthalic anhydride diimide macrocyclic compound,respectively,and the structure is characterized by nuclear magnetic resonance,mass spectrometry and single crystal diffraction.The third is to design and synthesize two sensors,and to study the recognition of nitrate ions by fluorescence spectroscopy.The recognition mechanism of a general sensor is based on hydrogen bonding or metal coordination interaction,but this sensor is based on a chemical reaction.The nitration reaction between the sensor and the nitrate under mild conditions,then causes the fluorescence of the sensor to be quenched,thereby realizing the identification of the nitrate.The results show that the sensor S1 has good selectivity and anti-interference ability to nitrate,and its detection limit is 1.5×10^-7M.The selectivity and anti-interference ability of sensor S2 is relatively poor,and the detection limit is 1.32×10^-6 M.