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PL
Zbadano możliwość zastosowania 5,10,15,20-tertrakis-[-4‒2-(3-pentadecylofenoksy)-etoksy]fenyloporfiryny, jako chemosensora akceptorów elektronów: HCl, TFA i BF3, w fazie stałej, w postaci cienkiej warstwy na nośniku szklanym oraz w fazie ciekłej w benzenie. W widmie UV-Vis chemosensora pod wpływem akceptora następują charakterystyczne zmiany w położeniu pasm, połączone ze zmianą barwy układów. Wskazuje to na dużą wrażliwość porfiryny na działanie badanych akceptorów.
EN
The possibility to use 5,10,15,20-tetrakis-[-4–2-(3-pentadecylphenoxy)-ethoxy]phenylporphyrin as a chemosensor for the detection of electron acceptors: HCl, TFA and BF3 in solid-phase in the form of thin film on glass carrier plate and in liquid phase in benzene. When chemosensor is under the influence of acceptor, the characteristic changes occur in the position of bands in its UV-VIS spectrum accompanied by the change of system colour. This indicates high sensitivity of porphyrin to action of studied acceptor systems.
2
Content available Porfiryny zamknięte w żelu krzemionkowym
EN
The need for new, chemically and physically stable luminescent materials operating with UV excitations has stimulated research on luminescence properties of doped sol–gel material. In this work, it has been presented a technology of production of silica gels doped with organic molecules, lanthanide compounds and organic/inorganic composites. Optical properties of these materials as functions of temperature, concentration and excitation wavelength are presented. Dynamics of excited states has been discussed based on the decay times and emission efficiencies data. Mechanisms of ligand-to-metal energy transfer as well as other processes affecting emission efficiency are considered. Silica sol–gels doped with di-aminoacid derivatives of porphyrins: PP(Ser)2(Arg)2, PP(Ala)2(Arg)2, PP(Met)2(Arg)2, where Met, Arg and Ser denote methionine, serine and arginine aminoacids, respectively, and H2TTMePP {tetrakis[4-(trimethylammonio)phenyl]-21H,23H-porphine} have been obtained and spectroscopically studied. These materials can find applications as phosphors or sensors of UV irradiation.
3
Content available remote Synteza koroli
EN
Corroles, one carbon shorter analogues of porphyrins emerged a few years ago as an independent research area (Fig. 1) [1-3]. Their coordination chemistry, photophysics, synthesis, chemical transformations, electrochemistry and other properties have recently been studied in great detail [7-11]. Discovered in 1964 [15], for many years they have been mainly synthesized via a,c-biladienes cyclization [19-20]. Multistep a,c-biladienes preparation discouraged broader range of chemists from studying corroles (Scheme 2). Since initial reports by Gross [17, 18] and Paolesse [16] revealing one-pot syntheses of meso-substituted corroles from aldehydes and pyrrole, this reaction has been subjected to many refining studies (Scheme 4, 5; Table 2) [23-28]. As a result yields have been improved to ~ 15%. The one-pot synthesis of meso-substitued A3-corroles from aldehydes and pyrroles consists of two independent steps. The first step is an acid-mediated electrophilic substitution to yield a mixture of various aldehyde-pyrrole oligocondensates including bilane (tetrapyrrane) - the direct precursor of corrole (Scheme 6). The second step is the oxidative ring-closure. Maximizing bilane formation while minimizing the formation of dipyrromethanes, tripyrrane and higher oligocondensate is a difficult task due to the similar reactivity of all these compounds [30-32]. Recently new and efficient conditions for the synthesis of meso-substituted corroles have been developed [33]. The first step, namely the reaction of aldehydes with pyrrole, was carried out in a water-methanol mixture in the presence of HCl. A relatively narrow distribution of aldehyde-pyrrole oligocondensates was controlled by their solubility in the reaction medium. After thorough optimization of various reaction parameters high yields of bilanes were obtained. As a result, many A3-corroles were obtained in the highest yield (~25-30%) reported to date. Corroles bearing two various substituents at meso positions were synthesized for the first time from dipyrromethanes and aldehydes (Scheme 10) [35]. This method continues to prevail in the literature [36-38]. Performance of this reaction in H2O/MeOH/HCl mixtures allows to obtain trans-A2B-corroles in yields up to 56% (Scheme 11) [33]. Last developments in the chemistry of corroles make these compounds more accessible than respective porphyrins.
4
Content available remote Pochodne porfiryn zawierające fragment acetylenowy
EN
The monograph gives a review of literature on porphyrinoids containing an ace-tylene unit attached at macrocyclic perimeter or built into a coordination core. The inclusion of an acetylene fragment provides an unusual structural motif because of its symmetrical cylindrical structure, coordination ability towards metal ions and reactivity. The synthesis, coordination properties and reactivity of porphyrin analogs with an ethynylene unit embedded in the macrocyclic skeleton have been described. Most of such macrocycles belong to stretched porphycenes and heteroporphycenes [8, 9]. The distinct class of expanded porphyrin analogs is delivered by very stable cyclooligothiophenediacetylenes with different size of the interior cavity [16]. A novel type of contracted heteroporphyrins namely dithiaethyneporphyrins, with an acetylene moiety introduced instead of one of pyrrole units, has been also characterized [17, 18]. These macrocycles display unique features of an [18]triphyrin(4.1.1) frame. The introduction of an alkyne moiety outside porphyrinic macrocycle yields meso- or B-alkynylporphyrins [38-42, 71-75]. The synthetic pathways and spectroscopic properties of alkynylporphyrins are included in the second part of the presented review. These macrocycles are widely used as building blocks in the construction of conjugated oligomeric and polymeric porphyrins and metalloporphyrins [81-85, 89-93]. Moreover, the paper provides classification of such ? conjugated systems, which are extensively explored in the analysis of charge or electron density transfer due to the strong electronic conjugation of acetylene with the [pi] system of the porphyrin ring.
EN
The thermodynamic parameters for interactions of Ph2SnCl2 and Ph2SnBr2 with para-substituted meso-tetraphenylporphyrins (H2T(4-X)PP; X = OCH3, CH3, H, Cl) have been studied. The formation constants have been calculated using UV-Vis titration spectra and computer SQUAD program. The adducts show the composition 2:1 of Ph2SnX2 to porphyrin. Formation constants decreased with decreasing electron donation of porphyrins and with decreasing electron withdrawing property of X group on the diphenyltin compound, as follow: H2T(4-OCH3)PP > H2T(4-CH3)PP > H2TPP > H2T(4-Cl)PP; and Ph2SnCl2 > Ph2SnBr2.
6
Content available remote Chemistry of quaternary azaaromatics and related species
EN
In the present review dealing with quaternary azaaromatics three first chapters concern their syntheses, reactivity and physicochemical properties. The fourth and fifth chapters are devoted to viologens and to selected examples of supramolecular systems, respectively. In three final chapters the possible applications and bilogical activities of quaternary azaaromatics are presented along with porphyrins bearing quaternary azaaromatic moieties.
PL
W artykule na temat czwartorzędowych związków azaaromatycznych w pierwszych trzech rozdziałach omówiono ich syntezy, reaktywność i właściwości fizykochemiczne; w czwartym i piątym rozdziale przedstawiono wiologeny i wybrane przykłady supramolekularnych układów. W końcowych rozdziałach opisano możliwości zastosowań i czynność biologiczną czwartorzędowych związków azaaromatycznych oraz scharakteryzowano porfiryny zawierające takie układy.
7
Content available remote Zastosowanie reakcji kompleksowania metali porfirynami w analizie chemicznej
EN
The porphyrin molecules contain four pyrrole rings linked via methane bridges. They are tetradentate ligand, in which the space available for the coordinated metal ion has a maximum diameter of approximately 3.7 Å. Porphyrins and their complexes with metal ions play important role in several biological as well as catalytic systems. They are involved in dioxygen transport and storage, photosynthesis or electron transfer. Due to strong complexing properties and catalytic behaviour, porphyrins and metaloporphyrins have found numerous applications in analytical chemistry. Several porphyrins become useful as the high sensitive chromogenic reagents. The stable complexes between transition metals and porphyrin ligands enable coordinating interaction with additional ligands above and below the molecule plane, so these compounds are used as components of membranes of ion selective electrodes in potentiometry and voltammetry. Several porphyrins find applications as optical sensors and biosensors. Due to the mixed mechanism of interaction between porphyrin macrocycle and various solutes, porphyrins find interesting applications as stationary phases in HPLC for separation of aromatic carboxylates, sulfonates, polycyclic aromatic hydrocarbons, fullerenes as well as amino acids and peptides. In capillary electrophoresis these compounds found application as the derivatizing agents. Porphyrins could be also used as a modifier in solid phase extraction technique or the selective ligands for enrichment of some transition metals.
PL
Nowe rozpuszczalne w wodzie fotosensybilizatory polimerowe zawierające chromofory porfiry-nowe Przedstawiono porównanie właściwości fotochemicznych dwóch amfifilowych polimerów: statystycznego i blokowego kopolimeru styrenosulfonianu sodowego i 5-(4-akryloiloksy-fenylo)-10,15,20-tritoliloporfiryny [odpowiednio: PSSS-s-Po i PSSS-b-Po]. Wykazano, że oba kopolimery są efektywnymi fotosensybilizatorami, przy czym wydajność kwantowa fluorescencji chromoforów porfirynowych w przypadku PSSS-s-Po jest znacznie większa niż PSSS-b-Po. Mogą one wpływać na reakcje fotochemiczne zarówno w wyniku przekazu energii, jak i na drodze przeniesienia elektronu. W roztworze wodnym zawierającym kopolimer oraz 1,1-dipropylo-sulfonian wiologenu (PSV) osiągnięto trwałą separację ładunku. Zbadano również kinetykę reakcji fotoutleniania wielopierścieniowych związków aromatycznych (na przykładzie rubrenu) zsolubilizowanych w wodnym roztworze kopolimeru.
EN
A comparison of photochemical properties of two amphiphilic polymers: statistical and block copolymers of sodium styrenesulfonate and 5-(4-acryloyloxyphenyl)-10,15,20- tritolylporphyrin [PSSS-s-Po and PSSS-b-Po, respectively - Formula (I)] is presented. It was demonstrated that both copolymers act as effective photosensitizers. Fluorescence quantum yield of porphyrin chromophores; of PSSS-s-Po is much higher than of PSSS-b-Po. They can influence the photochemical reactions via energy transfer or electron transfer. The efficient charge separation in the aqueous solution containing the copolymer and viologen 1,1'-dipropylsulfonate was reached. The kinetics of the reaction of the photooxidation of polycyclic aromatic compounds (such as rubrene), solubilized in aqueous solution of the copolymer, was also investigated (Fig. 3).
PL
W artykule omówiono budowę pierścienia porfirynowego i jego analogu - pierścienia ftalocjaninowego. Omówiono najważniejsze reakcje tych makrocykli: protonowania, kompleksowania metali, aglomeracji, przyłączania podstawników oraz redukcji i utleniania.
PL
Coraz szybsze tempo rozwoju współczesnej cywilizacji opiera się przede wszystkim na wprowadzaniu nowych, efektywniejszych i bardziej skomplikowanych technologii. Nowe technologie natomiast wymagają nowych i bardziej użytecznych rozwiązań. Jednym z nich jest na pewno zastosowanie materiałów organicznych, lekkich, wykazujących zdolności przewodzące i łatwo ulegających procesowi chemicznej modyfikacji. Unikalne połączenie właściwości fotoaktywnych oraz zdolności do przenoszenia elektronów, predestynuje do tego celu jedną z grup złożonych związków makrocyklicznych - porfiryny oraz ich analogi - ftalocyjaniny.
EN
Four new mono-ribosyl derivatives (5, 6, 9, and 11) and one four-ribosyl derivative (12) were synthesized. Complexes of a few of these compounds with metals were also synthesized. All compounds were characterized by spectroscopic methods
EN
In the paper structure and properties of chosen porphyrin derivatives are presented, along with possibilities of their applications.
PL
W artykule przedstawiono budowę i właściwości pochodnych porfiryn, wraz z podaniem możliwości ich zastosowań.
PL
Pzedstawiono wyniki badań nad zastosowaniem współczesnej, instrumentalnej chromatografii cienkowarstwowej (TLC) do analiz próbek środowiskowych. TLC wykorzystano do oznaczeń zanieczyszczeń, jako techniką wstępnej selekcji próbek oraz do usuwania interferentów. Chromatogramy rozwijano metodą elucji izokratycznej i gradientowej elucji wielokrokowej w normalnym lub odwróconym układzie faz. Próbki wody i gleby skażono wybranymi zanieczyszczeniami, dobierano techniką ekstrakcji i oczyszczania, a następnie oceniano odzyski i błędy oznaczeń. Wykazano możliwość zastosowań TLC do zadań związanych z monitoringiem środowiska.
EN
In this paper the results of the application of the modern, instrumental thin-layer chromatography (TLC) for the analyses of environmetal samples polluted with chemical warfare agents, nitric compounds of military significance, and heavy metals were presented. The isocratic and automated multiple development elution have been used to develop chromatograms under the normal and reverse-phase conditions. A densitomeric technique for quantitation of analytes has been employed. Water and soil samples were polluted with compounds above mentioned, and techniques of extraction were selected, then recovery and errors were estimated. TLC has been shown to be useful for environmental monitoring.
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