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1

Ditlenek węgla w syntezie organicznej

Burczyk B.

Wiadomości Chemiczne

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2013

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[Z] 67, 1-2

1--53

EN

Carbon dioxide is an abundant, cheap, almost nontoxic, thermodynamically stable, inert electrophile. Exploitation of CO 2 as a chemical feedstock, although will almost certainly not reduce its atmospheric concentration significantly, aims to generate high-value products and more-efficient processes. In recent years efficient transition-metal complexes have been used to perform homogeneously catalyzed transformations of CO 2 . This paper presents an overview of available catalytic routes for the synthesis of carboxylic acids, lactones, urea and carbamates, linear and cyclic carbonates as well as polycarbonates. Reduction processes of CO 2 are shortly men - tioned as well. C arboxylic acids have been synthesized via : (i) carboxylation of organolithium, organomagnesium (Scheme 2 [35]), organoboron (Scheme 3 [40 -42]), organozinc (Scheme 4 [43, 44]) and organotin (Scheme 5 [45, 46]) compounds; (ii) oxidative cycloaddition of CO 2 to olefins and alkynes (Scheme 6 -10 [47 -50, 57]) catalyzed by Ni(0)-complexes; (iii) transition-metal catalyzed reductive hydrocarboxylation of unsaturated compounds (Scheme 11, 12 [64 -67]); (iv) carboxylation of C-H bond (Scheme 13 [69 -71]). Telomerization of dienes, for instance 1,3-butadiene, and CO 2 in the presence of Ni(II) and Pd(II) complexes leads to lactones and esters of carboxylic acids (Scheme 14, 15 [73 -79]). Nucleophilic ammonia, primary and secondary amines react with CO 2 to give, respectively, urea and carbamic acid esters - carbamates and isocyanates (Scheme 16 -18 [94, 95]), thus eliminating the use of phosgene in their synthesis. CO 2 reacts with alcohols, diols and epoxides in the presence of transition-metal complexes (Fig. 2) and the reaction products are: linear carbonates (Scheme 20, 21 [110 -118]), cyclic carbonates (Scheme 22 -24 [153 -170]) and polycarbonates (Scheme 25, 26, Fig. 3, Tab. 1 [179 -186]). Finally, hydrogenation of CO 2 , leading to the formation of CO, HCOOH, CH 3 OH, CH 4 , C 2 H 6 and C 2 H 4 (Scheme 27), as well as electrochemical and photochemical reductions in the pre - sence of homogeneous and heterogeneous catalysts have been shortly reviewed.

2

Koordynacyjne materiały wybuchowe

Bełzowski J., Wojewódka A., Romanowski M.

Chemik

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2010

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Vol. 64, nr 1

21-24

PL

Historia i rozwój materiałów wybuchowych sięgają około dwóch tysiącleci wstecz. Począwszy od prochu czarnego, poprzez nitrozwiązki i nitroestry, aktualne kierunki rozwoju dotyczą m.in. badań nad koordynacyjnymi związkami metali przejściowych, zwanych potocznie solami złożonymi. Prace te doprowadziły do otrzymania szeregu nowych struktur mających cechy materiałów wybuchowych, zarówno kruszących, inicjujących jak i miotających.

EN

The history and evolution of explosives reach about two millennia backwards. Starting form the black powder, thought nitro-compounds and nitro-esthers, current directions of researches concern coordination transition metal compounds, called compounded salt. This researches leads to a number of new chemical structures which posses explosive parameters, just like blasting or primary explosives and propellants.

3

Woda: użyteczne i nieszkodliwe dla środowiska naturalnego medium reakcyjne

Burczyk B.

Przemysł Chemiczny

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2007

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T. 86, nr 3

184-194

4

Kompleksy metali przejściowych immobilizowane na polimerach, jako katalizatory niektórych reakcji utleniana

Owsik I.A., Kolarz B. N.

Wiadomości Chemiczne

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2003

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[Z] 57, 1-2

21--42

EN

The survey applies to oxidation reaction of substituent phenols in the presence of catalysts. The transition metal complexes with various types of attached to polymer support ligands were used as these catalysts. Especially, we have paid attention to the hydroquinone oxidation to p-benzoquinone using hydrogen peroxide and atmospheric oxygen in the presence of Cu(II) complexes with ligands containing nitrogen (for example: pirydyl, aminoamidyl or guanidyl groups). Oxidation reactions of substituent phenols proceeds in accordance with Michealis-Menten kinetic in all of described systems. It can preclude neither an influence of support kind applied to the catalyst preparation nor an influence of ligand kind chelating metal ions on oxidation kinetic. The comparison of the oxidation kinetic in several systems showed the domination of polymer-metal complexes over the native metal ions and also over the catalysts being the metal complexes with the low molecular compounds (containing the same ligands as these, which were attached to polymer support).

5

Sililenowe kompleksy metali przejściowych

Maciejewski H.

Wiadomości Chemiczne

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2002

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[Z] 56, 11-12

953-981

EN

Major advance in organometallic chemistry in the last 15 years has been achieved in the area of silicometallics chemistry, based on silicon to metal multiple bonding and silicon with low coordination numbers. Research in this area has led to a discovery of fundamentally new classes of compounds, such as silylene, silene, silaimine, disilene or silacarbyne complexes. Many of these systems had been unknown prior to their synthesis, even as reactive intermediates. This paper provides a comprehensive review of the silylene transition metal complexes. The majority of metal - silylene complexes synthesised so far have required donor stabilisation via the addition of a Lewis base. The use of thermally stable bis(amino)silylenes as ligands has led to a synthesis of base-free, stable silylene metal complexes. The chemistry of these compounds is discussed under headings: types of silylene complexes, methods of their synthesis, structure and properties of TM silylene complexes and also their application to catalysis. Despite the fact that the stable silylene transition metal complexes have been known for less than a decade, the chemistry of these compounds has been comprehensively recognised.

6

Chemiczne i biochemiczne aspekty kompleksów mieszanych

Kroczewska D., Kurzak B.

Wiadomości Chemiczne

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2001

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[Z] 55, 3-4

263-287

EN

During the last two decades thousands of important papers and some excelant review concerning complex equilibria have been published. In fact, most of these papers concern data on complex equilibrium, which does not involve species other than simple complexes with a completely homogenous coordination sphere Because mixed-ligand complexes are the most general and probable forms of existence of the elements in solution, we would like to present the mixed-ligand complexes in the aspect of their role in chemistry and in living systems. In the first part of this text we have lain particular emphasis upon literature data which show that it is worthwhile to assemble information on the formation, stability, structure and on the mutual influence of two ligands bound to the same metal ion, in the next part - on biochemical processes (transport, storage, inhibition of anzyme processes) which might be simulated by mixed-ligand complexes as "model systems" and at last - on own studies upon the mixed-ligand complexes of hydroxamic acid (a- or b-alaninehydroxamic acid) and one of polyamines with different metal ions. In order to find the answer for the following question: what kind of stoichiometry, geometry and binding mode there is in complexes which arrive in studied ternary systems? We used different methods: pH-metric method and spectroscopic ones (UV-VIS, EPR and NMR). The results obtained in our investigations and presented in this text show that the steric effect plays a very important role in the formation of the mixed-ligand complexes. In the case of bulky polyamine bonded in the zink(II) equimolar complex the coordination of a- or b-alaninehydroxamic acid is more favoured than the second polyamine ligand. There is no mixed-ligand complex formation in the case of ternary sestems with nickel(II). The reason for this is in the geometry of parent complexes - octahedral for nickel(II)-amine and square planar for nickel(II)-a-Alaha systems. The tridentate coordination of diethylenetriamine results in five-coordinated mixed-ligand copper(II) complexes in which the aminohydroxamate moiety adopts an equatorial-axial coordination mode.

7

Badania równowagowych reakcji kompleksowania jonów metali przejściowych z wybranymi bioligandami

Masłowska J., Kucharska U., Owczarek A., Janiak J., Duda J., Łącka A.

Zeszyty Naukowe. Chemia Spożywcza i Biotechnologia / Politechnika Łódzka

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2000

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Z. 64

77-94

PL

Opisano wyniki badań fizykochemicznych nad reakcjami równowagowymi, reakcjami kompleksowania w wybranych układach zawierających jony metali oraz odczynniki kompleksotwórcze, takie jak: kwas foliowy lub askorbinowy, barwniki oraz inne. W oparciu o badania spektralne i elektrochemiczne wykazano przebiegające procesy tworzenia się kompleksów oraz zbadano ich skład oraz termodynamiczną trwałość. Zaproponowano także budowę zbadanych połączeń oraz przedyskutowano charakterystyczne cechy ich struktury.

EN

Independent methods for the identification of new complexes ionic metals Fe(II), Cu(II), Mn(II), Mg(II), Ca(II), Be(II) with bioligands as vitamins, dyes, aminoacids, thioaminoacids and thers have been stated. The absorption spectra of the systems were characterised by intensive absorption bands within both the UV range and VIS range. The determination values of potentials (Ep) and peak currents (I) versus pH of solution are given in Tables. The paper contains the experimentally found values of stability constants of the new complexes. During further stage of our studies, these complexes will be used to determine ionic metal content in foods.

8

Early transition metal complexes containing aminopyridinato ligands - coordination chemistry, organometallic chemistry and catalysis

Kempe R., Oberthur M., Hillebrand G., Spannenberg A., Fuhrmann H.

Polimery

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1998

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T. 43, nr 2

96-104

EN

Early transition metal complexes containing aminopyridinato ligands have been reported only rarely. Such ligands combine a number of virtues which make them unique in the early transition metal chemistry. Besides the great variety of substitution patterns enabling us to fine tune electronic and steric features, they impress us with the flexibility in the bind-ing mode covering the whole range from a pure amido metal bond up to a delocalized Namido-Cipso-Npyridine-M four members ring. Coordination chemistry, organometallic chemistry and some selected applications in homo-geneous catalysis including olefin polymerization are reviewed.

PL

Przedstawiono przegląd problemów chemii koordyjacyjnej wymienionych w tytule kompleksów metali przejściowych grup 3-6 skoordynowanych z atomami azotu oraz problemów chemii związków metaloorganicznych w odniesieniu do kompleksów metali grupy 3 i 4 z ligandami aminopirydynatowymi. Scharakteryzowano też przebieg katalizowanych przez omawiane kompleksy polimeryzacji olefin z zastosowaniem różnych kokatalizatorów glinoorganicznych (metyloaluminoksanu, i-Bu3Al, Et3Al2Cl3) oraz polimeryzacji z otwarciem pierścienia laktamów.