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Ciecze jonowe w metatezie olefin : wyzwania i bariery

Barteczko Natalia, Grymel Mirosława, Chrobok Anna

Przemysł Chemiczny

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2020

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T. 99, nr 6

927--933

PL

Metateza olefin stanowi jedno z najskuteczniejszych narzędzi syntezy organicznej w ostatnich latach. Ciecze jonowe (IL) ze względu na ciekawe właściwości, takie jak mała prężność par, możliwość projektowania oraz duża zdolność rozpuszczania szerokiej gamy związków organicznych, nieorganicznych i metaloorganicznych, stosowane są w reakcjach metatezy jako alternatywne rozpuszczalniki wobec różnych układów katalitycznych. Przedstawiono przykłady zastosowania IL w metatezie olefin, a także związane z tym wyzwania i bariery.

EN

A review, with 71 refs., of ionic liqs. used in olefin metathesis as alternative solvents.

2

Katalizatory metatezy olefin, modyfikacje liganda NHC

Retajczyk M., Wróblewska A.

Wiadomości Chemiczne

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2017

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[Z] 71, 5-6

323--347

EN

Olefin metathesis is one of the most important synthetic tools, both in organic and olefin chemistry. Olefin metathesis allows to shorten production time of organic compounds and it is characterized by a smaller amount of by-products and waste in comparison with the classical ways of the synthesis of these compounds. Simultaneously, the conditions at which metathesis is performed are environmentally friendly. This method allows obtaining very valuable compounds, such as: anti-inflammatory agents, fungicides and many others. This causes that olefin metathesis has an important place in the organic synthesis and develops constantly. The first catalysts had undefined structure, therefore, it was difficult to predict the mechanism of their action. Big development metathesis came with the synthesis of catalysts with a clearly defined structure. This article explains what olefin metathesis is and shows applications of olefin metathesis. This work presents catalysts, which possess transition metal in the structure, such as: ruthenium, molybdenum or tungsten. It also shows the comparison of catalysts possess ruthenium (Grubbs catalyst first and second generation and Hoveyda-Grubbs catalyst) taking into account their structure and properties. This work describe carbenes, which improve thermal stability of catalysts compare with complexes containing phosphine. Researchers receive new compounds through modifications on the NHC ligand. In this work are presented modifications of the NHC ligand complexes of ruthenium described in the literature and their influence on such catalytic properties as: activity, selectivity, and efficiency. Modifications concern: heteroatoms, bulky groups and groups, which change electron density. Despite many studies and receiving large amounts of catalysts for this reaction, still a problem is the obtaining of an universal catalyst for all types transitions, that would have a high activity, high efficiency and which could be easily recovered after the reaction.

3

Synteza i zastosowanie nowych katalizatorów metatezy olefin

Hryniewicka A.

Wiadomości Chemiczne

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2014

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[Z] 68, 11-12

961--980

EN

Olefin metathesis has emerged as a powerful tool for the formation of carboncarbon double bonds. The success of this methodology has spurred the intense investigation of new catalysts showing a better application profile. The syntheses and the application profiles of the seven new ruthenium metathesis catalysts have been described. Five of them were modified in benzylidene part with 6-hydroxychromane- and 2H-3,4-chromenemethylidene moiety. In chromanol – α-tocopherol model compound, some specific stereoelectronic effects have been observed. Introduction of this ligand to the catalyst may provide new advantageous properties. The other new catalysts contained modified N-heterocyclic carbene ligand (NHC), in which N,N’-mesityl substituents of NHC system were linked with diethylene glycol chain as a “clamping ring”. This ring would contribute to a steric shield of the NHC and ruthenium coordination center. Probably it may inforce a proper orientation of substituents in metallacyclobutane (all-cis), leading to Z-olefin formation. The obtained catalysts were investigated in model reactions: ring closing metathesis, cross metathesis and enyne metathesis. The experiments proved they efficiency. In many reactions the catalysts showed activity comparable or superior to that of commercially available Grubbs and Hoveyda 2nd generation complexes. Stereochemistry Z/E of the cross-metathesis products obtained using new and known complexes were similar as well. The catalysts were applied in the synthesis of a new type of α-tocopherol glycoconjugates. An efficient method of the synthesis Hoveyda 2nd type complexes starting from ruthenium trichloride was developed. It is possible to circumvent using special laboratory equipment and expensive reagents. Hoveyda type complexes can be achieved with very good yield in gram scale. Keywords:

4

Metateza olefin jako podstawa zrównoważonych technologii chemicznych

Marciniec B.

Przemysł Chemiczny

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2007

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T. 86, nr 1

15-23

5

Dobrze zdefiniowane rutenowe katalizatory metatezy olefin

Pietraszuk C.

Wiadomości Chemiczne

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2005

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[Z] 59, 5-6

405--467

EN

Olefin metathesis has become an important synthetic tool in organic and polymer chemistry. The family of ruthenium based catalysts tolerant of normal organic and polymer processing conditions and preserving their catalytic properties in the presence of the majority of functional groups has allowed a great number of new applications. The monograph gives a review of literature on well-defined ruthenium catalysts of olefin metathesis published till the end of 2004. The activity of catalytic systems based on different ruthenium complexes in metathetic reactions has been characterised. The methods of obtaining alkylidene complexes of ruthenium showing catalytic activity in olefin metathetic transformations have been described together with the reactions in which these compounds can be used as precatalysts. Because of a large body of literature data on Grubbs catalysts and their significance in synthesis, much space is devoted to them, including the methods of their synthesis and the known processes leading to their decomposition. Elements of the mechanism of olefin metathesis the presence of Grubbs catalysts of the 1st and 2nd generation are presented together with the consequences for designing of new catalysts of the process. The catalysts containing a chelating alkylidene ligand, in particular the Hoveyda-Grubbs catalysts arousing increasing interest and already commercially available, have been discussed. Moreover, the paper provides characterisation of the cationic alkylidene complexes described by Hoffmann, allenylidene, vinylidene and alkylidynehydride complexes described by Werner. Preliminary results on obtaining chiral alkylidene ruthenium catalysts and their use in the asymmetric synthesis are also presented. Regarding a number of prospective commercial applications of metathesis in organic synthesis, the current status of the study on heterogenization of alkylidene ruthenium complexes in order to obtain active and stable catalysts for multiple use was described. The paper ends with a list of the most important, in the opinion of the author, monographs and review works on the application olefin metathesis catalysed by well-defined alkylidene complexes in organic and polymer synthesis.

6

Badanie wpływu nośników o różnej kwasowości na aktywność heterogenicznych katalizatorów molibdenowych w metatezie olefin

Handzlik J., Ogonowski J., Sikora E., Vogt O.

Przemysł Chemiczny

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2002

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T. 81, nr 3

184-188