Dicopper(ii) complexes of a new di-para-xylyldioxatetraazamacrocycle and cascade species with dicarboxylate anions: thermodynamics and structural properties
Über die umsetzungen von terephthalaldehyd mit aliphatischen diaminen. 431. Mitteilung über makromolekulare verbindungen
摘要:
AbstractBei den Umsetzungen des Terephthalaldehyds mit aliphatischen Diaminen entstehen uneinheitliche Gemische relativ niedermolekularer, linearer Poly‐Schiffscher Basen. Mit ätherdiaminen und β,β′‐Diaminodiäthylamin hingegen werden vielgliedrige, dimere Ring körper erhalten, die durch überführung in Derivate charakterisiert wurden. Einer dieser Ringkörper geht beim Erhitzen in konzentrierter Lösung in eine makropolymere, lineare Poly‐Schiffsche Base über, die Faserstruktur zeigt. Diese ist in Lösung instabil und bildet den Ringkörper zurück.
Dynamic combinatorial chemistry methodology was used to obtain eleven new polyazamacrocycles derived from isophthalic and terephthalic aldehyde and alpha omega-diamine Simple templates such as alkali metal salts were found to amplify large macrocycles 45-membered [3+3]hexaazacrown and 60-membered [4+4]octaazacrown Parent imine libraries were converted Into corresponding secondary libraries of amines using a fast reduction protocol Methyl carbamate protection of amine group allowed convenient isolation of polyazamacrocycles in very good yields (C) 2010 Elsevier Ltd All rights reserved
Über die umsetzungen von terephthalaldehyd mit aliphatischen diaminen. 431. Mitteilung über makromolekulare verbindungen
作者:von H. Krässig、G. Greber
DOI:10.1002/macp.1955.020170110
日期:——
AbstractBei den Umsetzungen des Terephthalaldehyds mit aliphatischen Diaminen entstehen uneinheitliche Gemische relativ niedermolekularer, linearer Poly‐Schiffscher Basen. Mit ätherdiaminen und β,β′‐Diaminodiäthylamin hingegen werden vielgliedrige, dimere Ring körper erhalten, die durch überführung in Derivate charakterisiert wurden. Einer dieser Ringkörper geht beim Erhitzen in konzentrierter Lösung in eine makropolymere, lineare Poly‐Schiffsche Base über, die Faserstruktur zeigt. Diese ist in Lösung instabil und bildet den Ringkörper zurück.
Dicopper(<scp>ii</scp>) complexes of a new di-para-xylyldioxatetraazamacrocycle and cascade species with dicarboxylate anions: thermodynamics and structural properties
作者:Sílvia Carvalho、Rita Delgado、Michael G. B. Drew、Vítor Félix
DOI:10.1039/b700115k
日期:——
The new dioxatetraazamacrocycle (L1) was synthesized by a 2 + 2 condensation and characterized. Stability constants of its copper(II) complexes were determined by spectrophotometry in DMSO at 298.2 K in 0.10 mol dm−3 KClO4. Mainly dinuclear complexes are formed and the presence of mononuclear species is dependent on the counterion (Cl− or ClO4−). The association constants of the dinuclear copper(II) complexes with dicarboxylate anions [oxalate (oxa2−), malonate (mal2−), succinate (suc2−), and glutarate (glu2−)] were also determined by spectrophotometry at 298.2 K in DMSO, and it was found that values decrease with an increase of the alkyl chain between the carboxylate groups. X-Band EPR spectra of the dicopper(II) complexes and of their cascade species in frozen DMSO exhibit dipole–dipole coupling, and their simulation, together with their UV-vis spectra, showed that the copper centres of the complexes in solution had square pyramidal geometries though with different distortions. From the experimental data, it was also possible to predict the Cu⋯Cu distances, the minimum being found at 6.4 Å for the Cu2L1Cl4 complex and then successively this distance slightly increases when the chloride anions are replaced by dicarboxylate anions, from 6.6 Å for oxa2− to 7.8 Å for glu2−. The crystal structures of the dinuclear copper cascade species with oxa2− and suc2− were determined and showed one anion bridging both copper centres and Cu⋯Cu distances of 5.485(7) Å and 6.442(8) Å, respectively.