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Chemia bioortogonalna : nowa perspektywa dla chemii organicznej

Miszczak K.

Wiadomości Chemiczne

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2018

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[Z] 72, 9-10

703--722

EN

This work is about bioorthogonal chemistry as a chemistry of reactions taking place in the living, in particular human, organism environment. In the search for reactions that can occur under conditions, the focus is mainly on the reactions of molecules that do not occur naturally in the body. Then, to have any application, generally for the purpose of using this reactions to locate the accumulation spotes of the selected substance, one molekule is covalently bonded to the biomarker molecule, the second binds to the indicator molecule, which is frequently fluorescein. Among a numerous examples of reactions that were designed during the short history of bioorthogonal chemistry, there are mainly reactions involving organic azides, which are not naturalny present in the human body. An example of such a reaction is the Staudinger ligation. Subsequent modifications include mainly the 1,3-dipolar addition of azides to alkynes, catalyzed by copper(I) ions. The instability and toxicity of this catalyst has forced further innovations in bioorthogonal reactions. One of them is the use of alkynes with high angular stress, which causes a significant reduction in the activation energy of the process, that it is unnecessary to use a catalyst. Another example of the bioorthogonal reactions are Diels-Alder reactions. The interest in these reactions is not diminishing for several reasons. One of them is the fact that as a result of a simple reaction two new carbon-carbon bonds (or others, for the HDA reaction) occur. Furthermore, many of these reactions occur at standard temperature, without additional heating. Moreover, the possibility of numerous modifications of the skeleton and functional groups and the substituents of dienes and dienophils facilitates carrying out these reactions in the aquatic environment. At the end, the article presents examples of the application of cyclooaddition reactions in bioorthogonal chemistry.

2

Chiralna ciecz jonowa na bazie n-(2-hydroksyetylo) pirolidyny i jej zastosowanie w reakcji Dielsa-Aldera

Gano M., Janus E.

Chemik

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2016

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Vol. 70, nr 9

503--508

PL

Otrzymano chiralną pirolidyniową ciecz jonową, zawierającą w kationie przy azocie podstawnik hydroksyetylowy i chiralny podstawnik (1R,2S,5R)-(-)-2-izopropylo-5-metylocykloheksyl- 1-oksymetylowy. Ciecz tę zastosowano następnie, jako rozpuszczalnik w reakcji Dielsa-Aldera nienasyconych aldehydów i ketonów z cyklopentadienem. Uzyskano umiarkowane do wysokich konwersje dienofili w środowisku cieczy jonowej lub stosując do cieczy jonowej dodatek kwasu Lewisa – Cu(OTf)2 lub Zn(OTf)2. Wpływ cieczy jonowej i układów katalitycznych na diastereoselektywność zależał od struktury dienofila.

XX

Chiral pyrrolidinium ionic liquid, with hydroxyethyl and (1R,2S,5R)-(-)-2-isopropyl-5-methylocyclohexyl-1-oksymethyl substituents at nitrogen atom was synthesized. Furthermore, this ionic liquid was used as solvent in the Diels-Alder reaction of unsaturated aldehydes and ketones with cyclopentadiene. Moderate to high conversion of dienophiles was obtained in this ionic liquid or in the presence of Lewis acid – Cu(OTf)2 lub Zn(OTf)2 that were dissolved in chiral ionic liquid. Effect of ionic liquid and catalytic systems on diasteroselectivity was dependent on the structure of dienophile.

3

Sprzężone nitroalkeny jako komponenty nieuzgodnionych reakcji Dielsa-Aldera – najnowsze doniesienia

Jasińska E., Dresler E., Łapczuk-Krygier A., Kącka A., Nowakowska-Bogdan E., Jasiński R.

Chemik

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2015

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Vol. 69, nr 7

395--400

PL

W pracy przedyskutowano najnowsze doniesienia dotyczące możliwego, nieuzgodnionego przebiegu reakcji Dielsa-Aldera z udziałem sprzężonych nitroalkenów.

EN

In the publication the recent progres concerning non-concerted Diels-Alder reactions with conjugated nitroalkenes has been discussed.

4

Selektywne usuwanie herbicydów z wody z użyciem modyfikowanego polidiwinylobenzenu

Kica M., Ronka S.

Czasopismo Techniczne. Mechanika

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2012

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R. 109, z. 9-M

111--120

PL

W artykule przedstawiono metodę usuwania herbicydów z roztworów wodnych w wyniku adsorpcji na polidiwinylobenzenie zmodyfikowanym w reakcji cykloaddycji Dielsa–Aldera. Zastosowane zostały adsorbenty różniące się wielkością powierzchni właściwej oraz zawartością grup umożliwiających sorpcję specyficzną, dzięki czemu określony został wpływ oddziaływań pomiędzy adsorbatem a adsorbentem na wydajność procesu.

EN

In the paper selective herbicides removal from water by adsorption using modified poly(divinylbenzene) was presented. Applied adsorbents were characterized by varied surface area and content of groups causing specific sorption. Due to that, impact of interactions between adsorbent and adsorbate on process efficiency was defined.

5

Mg(OTf)2 + ionic liquid – recyclable catalytic system in diels-alder reaction

Bittner B., Milchert E., Janus E.

Polish Journal of Chemical Technology

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2010

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Vol. 12, nr 3

3-5

EN

A comparative study of Diels-Alder reaction between cyclopentadiene and dimethyl maleate in catalytic system is reported. The catalytic system was formed from ionic liquid which was made of N-hexylpyridinium bis(trifluoromethylsulfonyl)imide and magnesium trifluoromethanesulfonate. The yields, TONs, TOFs and endo:exo ratios were calculated. The optimal catalyst concentration was found in order to obtain the mixture of endo, exo isomers with the highest yields. Moreover recycling of the catalytic system consisting of Mg(OTf)2 (2 mol%) and ionic liquid was performed. The distillation was noticed to be a better product removal method than extraction by organic solvent, taking into consideration both the TON and TOF values.

6

Mechanistyczne aspekty nieuzgodnionych (4+2)[pi]-elektronowych cykloaddycji

Jasiński R., Kwiatkowska M., Barański A.

Wiadomości Chemiczne

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2007

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[Z] 61, 7-8

485-514

EN

In this work the reported in literature (4+2)[pi]-electron cycloadditions, where a two-step mechanism was postulated and more or less thoroughly documented, has been subjected to a critical analysis. The research has been focused on [2+3] and [2+4] cycloadditions. To-date not many detailed studies, which would lead to unambiguous conclusions have been performed in this area. The two-step reaction mechanism of thiocarbonylylides with 1,2-dicyanoethene derivatives, [pi]-deficient cyclic ylides with 1-(dimethylamino)-propyne and 1,1-dimethoxy-1,3-butadiene with [pi]-deficient ethene derivatives can be considered as the most documented ones. On the other hand, the reports where a non-concerted mechanism of [2+3] cycloaddition of nitrile oxides with dideuteroethenes and [2+4] cycloaddition of 2-methylfurane with 1,2-dicarboxyethene was postulated are less reliable.

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Ionic liquids as powerful media in lanthanides triflate catalysed Diels-Alder reactions between cyclopentadiene and dimethyl maleate

Dramska A., Janus E.

Polish Journal of Chemical Technology

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2006

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Vol. 8, nr 2

9-11

EN

1-Butyl-3-methylimidazolium trifluoromethanesulfonate has been tested as a reaction medium in the Diels-Alder reaction between cyclopentadiene and dimethyl maleate. The effect of three Lewis acids - scandium triflate Sc(OTf)3, yttrium triflate Y(OTf)3 and ytterbium triflate Yb(OTf)3 on the yield and the endo/exo product ratio has been investigated. All the catalysts immobilized in [BMIM][OTf] were recycled without a significant decrease in the yields and the endo/exo ratio.

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Diels-AIder reaction between cyclopentadiene and dimethyl maleate in ionic liquids

Mazurkiewicz A., Janus E., Antoszczyszyn M.

Polish Journal of Chemical Technology

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2004

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Vol. 6, nr 2

31-34

EN

The reaction between cyclopentadiene and dimethyl maleate was carried out in the ionic liquids (1-alkoxymethyl-3-methylimidazolium salts) or in their mixture with the organic solvent. The effect of the length of the alkoxy substituent and the type of anion (BF4-, PF6-) on the yield of the product, the endo/exo ratio and the reaction rate constant (k2) were studied. The activity of the scandium triflate in the Diels-AIder reaction carried out in various reaction medium (methylene chloride, diethyl ether, methanol, 3-methyl-1-pentyloxyimidazolium tetrafluoroborate) was established.

9

Synteza wielofunkcyjnych pochodnych tiopiranu w reakcjach cykloaddycji Dielsa-Aldera

Bogdanowicz-Szwed K., Budzowski A.

Wiadomości Chemiczne

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2003

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[Z] 57, 5-6

435--457

EN

The hetero-Diels-Alder (HDA) methodology employing -unsaturated thiocarbonyl compounds represents a straightforward and efficient approach to sulfur-containing six-membered heterocycles. This review presents applications of α,β-unsaturated thiocarbonyl compounds in heterodiene reactions and covers the literature published in the last two decades. The α,β-unsaturated thiocarbonyl compounds, formally present 1-tia-1,3-butadiene system and include the following groups of compounds: thiochalcones, enaminothiones, α,β-unsaturated thioamides and compounds containing thiocarbonyl groups conjugated with carbon-carbon double bonds of carbo- and heteroaromatic rings. In general, reactions of 1-tia-1,3-butadiene systems with dienophiles belong to cycloadditions with normal electron demand, although there are some examples of cycloadditions with inverse electron demand. The first chapter concerns the cycloadditions of thiochalcones. Most of them are synthesized from chalcones in reactions with Lawesson reagent. Thiochalcones are unstable, at room temperature they are in equilibrium with two dimeric forms: thiopyran and 3,4-dihydro-1,2-dithiin. Both compounds are formed by heterodiene cycloaddition of two molecules of thiochalcone. At higher temperatures the dimers undergo decomposition to thiochalcones. Thiochalcones generated in situ by heating the dimers were successfully used in cycloadditions to acryloamide, styrene and enol ethers well as in an asymmetric hetero Diels-Alder (AHDA) reactions with (-) dimenthyl fumarate and in the reactions catalyzed by ytterbium triflate. The next chapter deals with the reactions of enaminothiones. These compounds reacted smoothly with dienophiles containing electron withdrawing groups yielding cycloadducts in high yields. Some cycloadducts easily eliminated amine furnishing stable 2H-thiopyran derivatives. Reactions of enaminothiones with substituted b-nitrostyrenes proceeded in region- and stereoselective manner. In contrast to enaminothiones, α,β-unsaturated thioanilides were found to be less reactive in hetero-Diels-Alder reactions. Two molecules of thiocinnamamide underwent cycloaddition in acetyl chloride yielding N-acylated derivative of 3,4-dihydro-2H-thiopyran. N-acylated α,β-unsaturated thioanilides was successfully used in heterodiene reactions with N-phenylmaleimide, cyclopentene and enol ether. A recent applications of N-acylated α,β-unsaturated thioanilides deal with intramolecular hetero-Diels-Alder reactions leading to tricyclic thiopyran derivatives. The compounds containing thiocarbonyl group conjugated with carbon-carbon double bond of furan or thiophene skeleton undergo cycloaddition with maleic anhydride, cyclopentene and norbornene yielding fused 2H-thiopyran derivatives in good yield. Some of the cycloadducts are unstable and spontaneously rearrange to aromatized compounds. An application of some organometallic reagents e.g. (Me2Al)2 S in thionation of aromatic ketones extended their use to synthesis of various thiopyrans via hetero-Diels-Alder reactions.