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Zastosowanie zielonych rozpuszczalników w syntezie nienasyconych związków boro- i krzemoorganicznych na drodze reakcji hydrometalacji i sprzęgania Marcińca

Walkowiak Jędrzej

Wiadomości Chemiczne

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2021

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[Z] 75, 1-2

111--136

EN

Unsaturated organoboron and organosilicon compounds constitute an important class of organometallic compounds, which due to the presence of silyl- or boryl- group attached to Csp2 atoms, their simple and straightforward transformations in coupling and demetallation reactions, found a broad range of applications in the synthesis of fine chemicals or new materials with tailored properties. Such compounds might be synthesized in many transformations but two of them: hydrometallation and Marciniec coupling reactions permitted to obtain compounds with high effectivity, selectivity, and in the case of hydrometallation reactions with excellent atom economy. Most of these processes occur in a homogeneous phase, which ensures excellent yields and stereo- and regioselectivity. On the other hand, such conditions generate problems with catalyst reuse, product separation, and substantial consumption of toxic, volatile organic solvents. According to the assumptions of sustainable development in chemistry, the new procedures, which allow to intensify the process in terms of its efficiency, according to green chemistry rules are of prior importance in modern chemical industry. In this manuscript, the newest achievements in the application of green solvents (ionic liquids, liquid polymers, and supercritical CO2) in catalytic hydrometallation of alkynes and coupling of vinylmetalloids with olefins are discussed. Such an approach builds a new strategy for effective catalyst immobilization and its reuse, the increase of process productivity by the application of repetitive batch processes, and elimination of organic solvents, typically used in these transformations. Selected contributions in this field of chemistry are presented within this review.

2

Kompleksy platyny typu Markó zawierające n-heterocykliczne ligandy karbenowe o właściwościach supersterycznych

Bolt Małgorzata, Żak Patrycja

Wiadomości Chemiczne

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2021

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[Z] 75, 1-2

31--53

EN

Progress in technology implying increasing demand for advanced materials dedicated for specific application has become a driving force stimulating research in different branches of science. It has been estimated that over 90% highly processed compounds have been obtained by the methods whose pivotal processes take place in the presence of catalysts based on transition metal complexes. Although these processes permit obtaining desired products, they are often charged with numerous drawbacks that prevent their implementation in industry. That is why the search for new catalytic systems ensuring high efficiency of final products and a possibility of reaction control is still an important direction of studies. Markó complexes are a group of platinum(0) coordination compounds of type [(NHC)Pt(dvtms)]. Although much attention has been recently attracted to these class of compounds, their number reported in hitherto literature is still limited. Owing to the possibility of wide modification of NHC carbene ligand attached to metal, the structures, and thus also properties, of the final complexes can be relatively easily matched to the requirements of individual catalytic reactions. It is particularly interesting in view of permanent development of new technologies and still increasing demand for new synthetic methods of more sophisticated materials dedicated to specific applications. In this paper, the synthesis and characterization of Markó type platinum(0) complexes containing bulky N-heterocyclic carbene ligands is described and their applications in the synthesis of new and unknown organic and organosilicon compounds are discussed. The main advantages of these complexes are highlighted providing an overview of this fascinating area of research.

3

Synteza liganda Sym-Phos {dicykloheksylo[3-(2,4,6-trimetoksyfenylo)-4-metoksynaft-2-yl]fosfina} i jego zastosowanie w reakcji Suzuki-Miyaura

Kielar K., Demchuk O. M.

Chemik

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2012

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Vol. 66, nr 6

585-594

PL

Przedstawiono tanią, szybką oraz wydajną trzyetapową syntezę odpornego na działanie powietrza ligandu Sym-Phos o C,P-typie kompleksowania. Sym-Phos tworzy skuteczne palladowe katalizatory, mające wykorzystanie w trudnych przypadkach reakcji sprzęgania krzyżowego, prowadzonych w przyjaznych środowisku warunkach (woda, otwarta kolba, umiarkowana temperatura).

EN

We present cheap, quick and efficient three-phase synthesis of air-resistant Sym-Phos ligand {dicyclohexyl[3-(2,4,6-trimethoxyphenyl)-4-methoxynaphth-2-yl]phosphine} of C,P-type complexes. Sym-Phos creates effective palladium catalysts to be used in difficult cases of cross-coupling reactions carried out under favourable conditions for the environment (water, unplugged flask, moderate temperature).

4

Kataliza homogeniczna

Rachwalik R., Ogonowski J.

LAB Laboratoria, Aparatura, Badania

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2010

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R. 15, nr 1

6-10

5

Hydrogenation of N-Heteroaromatic Compounds in the Presence of Soluble Metal Complexes

Borowski A.

Polish Journal of Chemistry

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2006

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Vol. 80, nr 2

205-226

EN

The review presents a concise discussion of reports on hydrogenation of N-containing heteroaromatic compounds in relation to the hydrodenitrogenation process (HDN), along with hydrogenation mechanisms of the most representative examples of the compounds studied. The influence of electronic properties of aromatic structures, with the special emphasis on the resonance stabilization energies and the interatomic C-C and C-N distances, on the susceptibility for their hydrogenation has been considered. The importance of an initial mode of substrate coordination in relation to the reaction products formed is underlined.

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Catalytic cycle of NOx conversion based on pentacyanoferrate complexes

Maciejowska I., Stasicka Z.

Bulletin of the Polish Academy of Sciences. Chemistry

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2002

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Vol. 50, No. 1

67-76

EN

Conversion of NO(x) + NH(3) to N(2), catalysed by the [Fe(II)(CN)(5)L]n- complexes (L= NO(+), NH(3), H(2)O proceeds through addition, comproportionation and substitution processes within the complexes and the reaction rates are sensitive to the different parameters. In this study the role of added cations was investigated and the main impact found concerned acceleration of the [Fe(CN)(5)NO](2)(2-) production from [Fe(CN)(5)L](3) (L= H(2)O, NH(3) and NO(2)(-) in alkaline medium. This could be achieved by increasing the amount ratio of [Fe(CN)(5)H(2)O] to its parent ammonia complex at given pH taking advantage from the specific cation effect on the rate of the [Fe(CN)(5)NH(3)](3) aquation. The rate wasaffected not only by concentration but also by the nature of the cation, i.e. by the hydratedradius of cation and its influence on the solution viscosity. The reaction of [Fe(CN)(5)NO](2-) with ammonia was re-examined in aspects of the pH dependent production of molecular nitrogen. The results are summarised in the overall photocatalytic cycle for which the optimal working pH range is limited to 10-11. The trend is consistent with the nucleophilic attack of NH(3)(+) on the N(NO) atom in [Fe(CN)(5)NO](2), followed by comproportionation within the N(NO)NH(+)(3) ligand, which results in N(2) generation.