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EN
Macrocyclic complexes continue to attract considerable attention due to their significance in biological systems, catalysis, medical diagnostics and other fields. While the most intensively studied macrocycles containing donor nitrogen atoms are tetraazamacrocycles such as porphyrins or cyclen derivatives, larger macrocyclic ligands containing up to 18 (or even more) donor atoms are also known. Due to their enlarged size, these macrocycles can bind large metal ions such as lanthanide(III) ions or bind multiple metal ions. In this review a subclass of large macrocycles will be discussed i.e. macrocyclic amines and imines that can be generated in the condensation of diamines with dicarbonyl compounds, in particular with 2,6-diformylpyridine or 2,6-diformylphenols. These macrocycles of various sizes lead to a rich variety of structures of metal complexes, including polynuclear complexes. Moreover, macrocycles derived from enantiopure trans-1,2- diaminocylohexane form chiral metal complexes that exhibit unusual effects such as helicity inversion, enantioselective self-recognition or enantiodiscrimination of organic guest molecules.
PL
Klasyczną metodę konwersji alkoholi pierwszorzędowych w odpowiednie halogenki alkilowe z użyciem trifenylofosfiny oraz tetrahalogenometanu, tzw. reakcję Appela, zaadoptowano do bezpośredniej syntezy terminalnych tioli i azydków organicznych pochodnych glikolu etylenowego oraz jego siarkowego analogu. W kluczowym etapie opisanej procedury one-pot, otrzymane in situ, w reakcji z N-bromosukcynimidem (NBS), odpowiednie dibromopochodne zostały przekształcone w związki docelowe w reakcji z nukleofilem siarkowym lub azotowym. Wybrane diazydki wykorzystano w syntezie nowych układów makrocyklicznych, które przetestowano pod kątem ich właściwości kompleksotwórczych.
EN
Classical method of conversion of primary alcohols into corresponding alkyl halides by usage of triphenylphosphine and tetrahalogenated methane, so-called Appel reaction, was adopted for the direct synthesis of terminal organic thiols and azides derived from ethylene glycol and its sulfurated analogue. In key step of the presented ‘one-pot’ protocol, corresponding dibromides, generated in situ via reaction with N-bromosuccinimide (NBS), were converted into desired products by treatment with appropriate sulfur or nitrogen nucleophile. A series of diazides and dithiols derived from (poly)ethylene glycols and their sulfur analogues were obtained. Selected diazides were utilized for the construction of novel macrocyclic systems, that were tested incontext of their complexing properties.
EN
Four bicyclic octaazacryptands and three triaza macrocyclic amines have been synthesized via the reaction of tris(aminoethyl)amine with six rigid aromatic dialdehydes, followed by reduction of the formed Schiff bases with sodium borohydride.
EN
The Suzuki-Miyaura coupling of 4- and 6-halosteroids affords good to excellent yields of potential aromatase inhibitors.While the reaction with 4- and 6-bromo derivatives is catalyzed by Pd(PPh3)2Cl2, the coupling with 6-chloro steroid (chlormadinone acetate) requires the use of Pd(dppb)Cl2 or Pd(dppf)Cl2. The palladium-catalyzed amination of bis(3-bromophenyl) ether of (5_)-cholane-3,24-diol with different polyamines leads to new macrocycles comprising one steroid and one polyamine fragments. Possibility of synthesis of macrocyclodimers containing two steroid and two polyamine fragments have been investigated.
EN
Seventeen new macrocyclic diamides and tetraamides have been synthesized via amidation reactions of three various methyl phenoxyacetates, readily available from simple dihydroxybenzenes, with alfa,omega-diamines in methanol or ethylene glycol as solvents.
EN
Four chiral macrocyclic bissulfonamides derived from D-mannitol and L-threitol, possessing C2 symmetry, were obtained by a macrocyclization reaction under high-dilution conditions. Their applications for alkali metal binding processes were studied using ESI-MS technique.
EN
Chiral alfa,omega,-diamines react under high-pressure conditions (10 kbar) with alfa,omega,-dicarboxylates to give chiral cyclic tetraamides having C2-symmetry. The alkali metal (Li+, Na+, K+, Rb+, and Cs+ ) binding selectivities of tetraamides are evaluated by way of electrospray ionization mass spectrometry. The ralative binding selectivities are estimated from the mass spectral intensities of the metal complexes.
8
Content available remote Synthesis of macrocyclic and linear oligomers of methyl a-D-mannopyranoside
EN
The polycondensation of methyl a-D-mannopyranoside (I) with 1,x-bis(2-formylphenoxy)alkanes (II) using various acid catalysts leads to the formation of macrocyclic compounds [1+1] and [2+2] and linear copolymer. NMR and ESI-MS studies demonstrated the evidence of structure of macrocyclic compounds. The structure of dialdehyde, the nature of the catalyst, and in particular, the molar ratio of catalyst to dialdehyde, show a very pronounced effects on yield of the resulting macrocycles.
PL
Otrzymano poliacetale o strukturze makrocyklicznej [1+1] [wzór (IIIa)] i [2+2] [wzór (IIIb)] oraz liniowe oligomery [wzór (IV)] w wyniku polikondensacji metylo-a-D-mannopiranozydu [wzór (I)] i dialdehydu - 1,x-bis(2-formylofenoksy)alkanu [wzór (II), gdzie x = 4, 5, 6, 8, 9, 10 i 12] katalizowanej kwasami (schemat A). Przedstawiono mechanizm tworzenia się cyklicznych acetali w reakcji katalizowanej kwasem (schemat B). Produkty polikondensacji charakteryzowano metodami 1H i 13C NMR (rys. 1 i 2, tabela 1) oraz ESI-MS (rys. 5). Zbadano wpływ budowy dialdehydu (rys. 3), rodzaju katalizatora (tabela 2), stosunku molowego dialdehyd:katalizator (rys. 4) oraz czasu reakcji (rys. 6) na wydajność tworzenia się związków makrocyklicznych w procesie polikondensacji. Największą wydajność makrocykli (>70 %) uzyskano w polikondensacji (I) z (II) o x = 4 lub 5. Najmniejszą zawartością makrocykli (2,2 %) dla (II) o x = 8 charakteryzował się poliacetal otrzymany w obecności wymieniacza jonowego "AmberlystŽ 15". Korzystny stosunek (II):p-TsOH wynosi 2:1, w takich warunkach wydajność makrocykli osiąga wartość ok. 60 %, dla (II) o x = 8. Zaobserwowano wzrost wydajności tworzenia makrocyli w ciągu 12 h; dalsze przedłużanie prowadzenia procesu nie powodowało zmian wartości wydajności.
EN
Five new macrocyclic compounds of the triazacoronand type have been synthesized, starting from dimethyl iminoacetate and appropriate _,_-diamines, in methanol as a solvent. Their complexing properties were investigated using the voltammetric method.
EN
The stable E- and Z-isomers of 10-membered azocrown ether have been isolated and studied by X-ray, 1H NMR and UV-Vis methods. Their structures in a solid state indicate the stretched conformation for trans-isomer and unstressed for cis-isomer. The concerted effect of azo-group _-conjugation with benzene residue and steric strain of molecular conformation results in the observed stability of isomers.
EN
A review is presented on macrocyclic compounds novel reagents for metal ions separation and removal in solvent extraction, transport through liquid membranes, and flotation processes. As macrocyclic compounds were used such chemicals as non-ionizable crown ethers, ionizable crown ethers (lariat ethers), calixarenes, and acyclic polyethers. Many literature data as well our own recent research data will be reported on metal ions removal and separation.
EN
34-membered macrocyclic hexaamine containing two independent N-3 donor sets forms homodinuclear transition metal complexes with cobalt(II), copper(II), and nickel(II). Titration experiments show that the homodinuclear complexes are formed exclusively without formation of mononuclear complexes. Displacements of anions within the copper(II) complexes occur easily upon addition of different anions to the CuCl2 complex. All new complexes are characterized by elemental analysis, IR and UV/VIS spectroscopy, and cyclic voltammetry. The dinuclear Cu(II) complex both in the solution and immobilized in Nafion layer on the electrode undergoes revesible l e reduction independently at each copper center and exhibits catalytic activity towards oxygen reduction.
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