32091-06-8

Upstream product

• 7168-95-8 2,3-dimethoxyterephthalic acid 
• 7169-12-2 2,3-dimethoxyterephthalic acid chloride 
• 506-59-2 N,N-dimethylammonium chloride 

Downstream Products

• 141946-87-4 1,4-bis(trimethylammoniomethyl)-2,3-dihydroxybenzene dichloride 
• 1141-11-3 1,4-bis(N,N-dimethylaminomethyl)-2,3-dihydroxybenzene dihydrochloride 

Relevant academic research and scientific papers

Azaparacyclophanes with Metal-binding Sites. Part 1. Preparation, Characterization, and Molecular Recognition Behaviour of Hexapus Azaparacyclophane and its Iron(III) Complex

All the catechol moieties of a hexapus triazaparacyclophane having three catechol moieties and six hydrocarbon chains (1) undergo coordination interactions with the iron(III) ion in a 1:1 molar ratio of 1 to iron(III) above pH 6 in an aqueous medium.Two different iron(III) complexes of 1, A and B in a 1:1 molar ratio, are in the high spin iron(III) state as characterized by electronic, EPR and Moessbauer spectroscopy: A is a hexacoordinated mononulear complex with half-protonated catecholato groups, subjected to considerable structural distortion; B is ahexacoordinated mononuclear complex with complete dissociation of all the catechol protons, retaining high structural symmetry.The molecular recognition behaviour of 1 and Fe-complex A toward hydrophobic guest molecules has been investigated in aqueous HEPES and acetate buffers at 30.0 deg C and μ 0.10 mol dm-3.The hexapus cyclophane 1 recognizes organic guests through hydrophobic and electrostatic interactions; anionic and non-ionic quests, 7-hydroxy-8-phenylazonaphthalene-1,3-disulfonate (OG) and 2-hydroxy-1-(2-pyridylazo)naphthalene (PAN), respectively, are incorporated into host 1 with binding constants of the order of 105 dm3 mol-1, while a cationic guest, 2-(p-dimethylaminostyryl)-1-ethylquinolinium (QR), is not included in the host.The guest-binding behaviour of Fe-complex A toward OG and PAN is much enhanced relative to that of 1 as effected by hydrophobic, electrostatic and coordination interactions under conditions identical to those applied to 1; the binding constant for OG is nearly pH-independent in a pH range of 3-8, while that for PAN is pH-dependent because the coordination interaction with the host is subject to change by pH.