pH-dependent complexation between pyridinyl-azacrown ether and amino-porphyrin was written by Shin, Kyung-ha;Shin, Eun Ju. And the article was included in Bulletin of the Korean Chemical Society in 2009.Recommanded Product: 1,4,7,10-Tetraoxa-13-azacyclopentadecane This article mentions the following:
Change of mode for the complex formation between amino-functionalized porphyrin ZnTTP-NH2 and pyridine-appended crown ether AzC-Py in the absence and presence of CF3COOH were investigated using absorption and fluorescence spectroscopy. To observe dual mode for complexation controlled by pH, axial coordination of pyridine ligand on zinc porphyrin and host-guest complexation between azacrown ether and ammonium cation was chosen. According to this respect, amino-functionalized porphyrin ZnTTP-NH2 and pyridine-appended crown ether AzC-Py were prepared In normal condition, pyridine moiety of AzC-Py coordinates axially on ZnTTP-NH2. With addition of AzC-Py, absorption and fluorescence spectra of ZnTTP-NH2 were greatly red-shifted and fluorescence intensity of ZnTTP-NH2 was remarkably increased. However, in acidic condition, ZnTTP-NH3+ was formed by the protonation of ZnTTP-NH2. Therefore, ammonium ion moiety of ZnTTP-NH3+ binds into azacrown ether cavity of AzC-Py, but axial coordination of pyridine appended crown ether on zinc porphyrin does not take place. In acidic condition, absorption and fluorescence spectra of ZnTTP-NH2 were only slightly changed with addition of AzC-Py. This shows the pH-controllable dual-mode complexation between zinc porphyrin and azacrown ether. In the experiment, the researchers used many compounds, for example, 1,4,7,10-Tetraoxa-13-azacyclopentadecane (cas: 66943-05-3Recommanded Product: 1,4,7,10-Tetraoxa-13-azacyclopentadecane).
1,4,7,10-Tetraoxa-13-azacyclopentadecane (cas: 66943-05-3) belongs to ethers. Of all the functional groups, ethers are the least reactive ones. Ether bonds are quite stable towards bases, oxidizing agents and reducing agents. Ethers can form hydrogen bonds with other molecules (alcohols, amines, etc.) that have O―H or N―H bonds. The ability to form hydrogen bonds with other compounds makes ethers particularly good solvents for a wide variety of organic compounds and a surprisingly large number of inorganic compounds.Recommanded Product: 1,4,7,10-Tetraoxa-13-azacyclopentadecane
Referemce:
Ether – Wikipedia,
Ether | (C2H5)2O – PubChem