The synthesis of cyclopolymers upon controlling the degree of macrocyclic polymerization,followed by the discovery of new properties has attracted increasing attention in supramolecular chemistry.Herein,a Schiff-base ...The synthesis of cyclopolymers upon controlling the degree of macrocyclic polymerization,followed by the discovery of new properties has attracted increasing attention in supramolecular chemistry.Herein,a Schiff-base condensation method performed at room temperature was used to control the formation of[1+1]and[2+2]macrocycles.In pure MeOH,the isomer[1+1]macrocycles were synthesized and organic particles such as dendritic,rods,and solid microspheres were directly precipitated from the reaction solution.The[1+1]macrocycles can be efficiently converted into their corresponding[2+2]macrocycles accompanied by the tunable morphology of the organic particles when n-hexane was added to the MeOH solution.Further studies showed that these organic particles have potential application toward the selective removal of Cd^(2+)ions with different adsorption ability in MeOH solution.展开更多
New [1+1] and 62-membered [2+2] Schiff base macrocycles containing a 2,6-diamidopyridine subunit have been synthesized by condensation reaction of the precursors pyridine-2,6-dicarboxamide and 1,10- bis(2'-formylp...New [1+1] and 62-membered [2+2] Schiff base macrocycles containing a 2,6-diamidopyridine subunit have been synthesized by condensation reaction of the precursors pyridine-2,6-dicarboxamide and 1,10- bis(2'-formylphenyloxy)decane in the presence of phosphoric acid via a one-pot process. The cyclo- condensed products were effectively isolated by gel column chromatography and characterized by 1H NMR, FTIR, mass spectrometry and X-ray analysis. The two macrocycles have a twisted structure, and not an open 'circular' conformation in the solid state.展开更多
A novel [1+1] Schiff-base macrocyclic compound 3 has been synthesized from precursor 1, 1,3-bis(2'- formylphenoxy)-2-propanol, and precursor 2, resorcinol-bis(4-aminophenyl)ether, via condensation and cyclizacti...A novel [1+1] Schiff-base macrocyclic compound 3 has been synthesized from precursor 1, 1,3-bis(2'- formylphenoxy)-2-propanol, and precursor 2, resorcinol-bis(4-aminophenyl)ether, via condensation and cyclizaction using Ba2+ as template. The macrocycle 3 was further reduced giving saturated macrocycle 4. The structures of 3 and 4 were characterized by elemental analysis, ~H NMR, IR, and MS spectra, and their structures were determined via single crystal X-ray diffraction studies. X-ray diffraction analysis revealed that the macrocyclic compound 3 has a folded conformation, and the corresponding reduced product 4 adopts a twisted and folded conformation due to its flexible nature. ~ 2013 Bi-Xue Zhu. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.展开更多
基金supported by the National Natural Science Foundation of China(Nos.21961007 and 21871063)the Science and Technology Foundation of Hunan Province(No.2020JJ2021).
文摘The synthesis of cyclopolymers upon controlling the degree of macrocyclic polymerization,followed by the discovery of new properties has attracted increasing attention in supramolecular chemistry.Herein,a Schiff-base condensation method performed at room temperature was used to control the formation of[1+1]and[2+2]macrocycles.In pure MeOH,the isomer[1+1]macrocycles were synthesized and organic particles such as dendritic,rods,and solid microspheres were directly precipitated from the reaction solution.The[1+1]macrocycles can be efficiently converted into their corresponding[2+2]macrocycles accompanied by the tunable morphology of the organic particles when n-hexane was added to the MeOH solution.Further studies showed that these organic particles have potential application toward the selective removal of Cd^(2+)ions with different adsorption ability in MeOH solution.
基金supported by the National Natural Science Foundation of China (No. 21061003)the ‘Chun-Hui’ Fund of Chinese Ministry of Education (No. Z2012054)
文摘New [1+1] and 62-membered [2+2] Schiff base macrocycles containing a 2,6-diamidopyridine subunit have been synthesized by condensation reaction of the precursors pyridine-2,6-dicarboxamide and 1,10- bis(2'-formylphenyloxy)decane in the presence of phosphoric acid via a one-pot process. The cyclo- condensed products were effectively isolated by gel column chromatography and characterized by 1H NMR, FTIR, mass spectrometry and X-ray analysis. The two macrocycles have a twisted structure, and not an open 'circular' conformation in the solid state.
基金supported by the National Natural Science Foundation of China(No.21061003)he International Collaborative Project of Guizhou Province(No.[2009]700104)the Natural Science Foundation of the Guizhou Province(No.(2012)2151)
文摘A novel [1+1] Schiff-base macrocyclic compound 3 has been synthesized from precursor 1, 1,3-bis(2'- formylphenoxy)-2-propanol, and precursor 2, resorcinol-bis(4-aminophenyl)ether, via condensation and cyclizaction using Ba2+ as template. The macrocycle 3 was further reduced giving saturated macrocycle 4. The structures of 3 and 4 were characterized by elemental analysis, ~H NMR, IR, and MS spectra, and their structures were determined via single crystal X-ray diffraction studies. X-ray diffraction analysis revealed that the macrocyclic compound 3 has a folded conformation, and the corresponding reduced product 4 adopts a twisted and folded conformation due to its flexible nature. ~ 2013 Bi-Xue Zhu. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.