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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.
EN
Six new chiral pyrolidinium salts with chiral substituent at quaternary nitrogen atom were synthesized with high overall yields from (-)-menthol as cheap chiral precursor and were identified by NMR and HRMS spectroscopy. It was shown that anion type had the effect on chemical shift of protons adjacent to quaternary nitrogen atom and physical properties of these salts. Salts with NTf2  or NPf2  were in a liquid state at room temperature and characterized with the highest thermal stability among others. Furthermore, chiral ionic liquid with NTf2  anion was used as solvent in Diels-Alder reaction and gave higher yield and stereoselectivity than in ionic liquids with achiral cations. Synthesized chiral salts have the potential as chiral solvents in synthesis and auxiliaries in analytical methods to improve chiral recognition.
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.
EN
A series of (5-chloro-2-thienyl)(3-(substituted phenyl) bicyclo [2.2.1] hept-5-en-2-yl) methanones have been synthesized by fly-ash catalyzed [4+2] cycloaddition Diels-Alder reaction of cyclopentadiene and 5-chloro-2-thienyl chalcones under cooling conditions. The yields of the methanones are more than 60%. The synthesized (5-chloro-2-thienyl)(3-(substituted phenyl) bicyclo [2.2.1] hept-5-en-2-yl) methanones are characterized by their physical constants and spectral data. The antimicrobial, antioxidant and insect antifeedant activities of synthesized methanones have been studied using their respective bacterial, fungal strains, DPPH radical scavenging activity and Dethler’s leaf-discs bioassay method.
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.
6
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.
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.
EN
Acidic ionic liquids based on trihexyltetradecylphosphonium chloride . P 6.6.6.14 Cl and six different metal chlorides (YCl 3 , YbCl 3 , MgCl 2 , ZnCl 2 , CuCl 2 , InCl 3 ) were prepared. The molar fraction of metal chloride (X MClx ) used for the formation of acidic ionic liquids with P 6.6.6.14 Cl was changed in the range from 0.3 to 0.5. The high catalytic activity in the Diels-Alder reaction of cyclopentadiene and various �ż,s-unsaturated carbonyl compounds showed ionic liquids at X MClx.0.4. In general, the highest product yields and endo:exo ratios were achieved in the acidic ionic liquids formed from MgCl 2 , YCl 3 and YbCl 3 . Thermogravimetric analysis suggested that the prepared ionic liquids were thermally stable up to nearly 400�‹C. Additionally, they could be reused with only little loss of catalytic activity after the 4th recycle.
EN
Controlled decomposition of sugar allyltin: methyl 2,3,4-tri-O-benzyl- 6,7,8- tri -deoxy-8-(tri-n-butyl)stannyl-alfa-D-gluco-oct-6(E)-eno-hexo-1,5-pyranoside af forded the corresponding dienoaldehyde with the D-xylo-configuration and the E-geometry across the internal double bond. Reaction of this intermediate with Ph3P=CH-CO2Me provided a triene, which under went cyclization to the bicyclic products: derivatives of bicyclo[4.3.0]nonatriene. Stereochemical aspects of this cyclization, as well as some transformations leading to carbobicyclic sugar mimics, are discussed.
10
Content available remote Mechanistyczne aspekty nieuzgodnionych (4+2)[pi]-elektronowych cykloaddycji
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.
PL
Przedstawiono wyniki badań doświadczalnych reakcji Dielsa i Aldera przebiegającej w cieczach jonowych, które zastosowano jako nowe możliwe do zawrócenia i przyjazne środowisku naturalnemu medium reakcji. Omówiono również sposoby przeprowadzania reakcji w cieczach jonowych z zastosowaniem dodatku katalizatorów trifluorometanosulfonianów skandu i litu, które użyto po raz pierwszy w reakcji Dielsa i Aldera pomiędzy cyklopentadienem i maleinianem dimetylu w cieczach jonowych.
EN
1-Butyl-3-methylimidazolium triflate (I), tetrafluoroborate, methylsulfate, and 2-(2-ethoxymethoxy)ethylsulfate were studied as recyclable solvent media for the Diels-Alder reactions (24 hrs. at 25°C) of (1/1.5 by moles) diMe maleate–cyclopentadiene, run without and with Sc triflate (or trifluoromethylsulfonimide) and Li triflate (or trifluoromethylsulfonimide) as catalysts. At reactants concns. of 4/6 mols/l., the yields were max. at 78–86% and the endo/exo isomer selectivities were 3.6–4.9; with catalysts used (1 mol% on maleate basis), 87–100% and 5.2–14.7, resp. Active only in I, Sc triflate raised the yield (from 42 to 61%), but not the selectivity. The Li catalysts were inferior. (I) was best as the solvent for the catalysts, and the Sc compds. were best as catalysts and gave the highest yields and selectivities. Products were extd. with Et2O. I was recovered nearly completely and recycled thrice with only minor losses in yield and selectivity.
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.
14
Content available remote Właściowści i zastosowanie kalafonii w przemyśle chemicznym
PL
Kalafonia jest surowcem naturalnym, pozyskiwanym z drzew sosnowych. W wyniku jej modyfikacji otrzymuje się wiele produktów, z których najbardziej użytecznym jest kwas maleopimarowy, otrzymywany w reakcji Dielsa i Aldera kwasów żywicznych i bezwodnika maleinowego. Na charakterystyczny skondensowany układ wielopierścieniowy kwasu maleopimarowego zwrócono szczególną uwagę w latach pięćdziesiątych XX w., a jego syntezę opracowano już w latach trzydziestych ub. stulecia. Uwzględniając szerokie możliwości zastosowania kwasu maleopimarowego oraz wykorzystanie nowoczesnych metod badawczych, podjęto prace nad modyfikacją syntezy kwasu maleopimarowego. Opracowano również nową metodę oczyszczania i metody analityczne, które umożliwiły potwierdzenie struktury otrzymanego produktu.
EN
A review with 48 refs. covering rosin modifications, esp. catalyzed heterogeneous polymerization and use of rosin’s functional groups to prep. fumaro-, acrylo- or maleopimaric (high-temp. programmed steps advised) acid.
15
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.
EN
Density Functional Theory (DFT) has been applied to study the concerted mechanism of the Diels-Alder reaction between 3-vinylcoumarin and ethylene, as well as their fluorinated analogues. The main goal was to establish the fluorine influence on reactivity and structure of transition state (TS) and predict the reaction path. Computations were performed at the B3LYP/6-31G* level, which allowed to optimise the structure of reactants and products.
EN
Thermal (215_C) extrusion of sulfur dioxide from 3-allyl-1,3-dihydro-2,1-benzisothiazole 2,2-dioxides (3-allylbenzosultams) leads to aza-ortho-xylylenes, which by [1,5] sigmatropic hydrogen shift transform into 1-(2-aminophenyl)buta-1,3-dienes. In the presence of dienophiles, N-phenylmaleimide (NPMI) or dimethyl fumarate, these dienes enter Diels-Alder reaction and the formed adducts transform into 6a,7,8,10a-tetrahydro-5H-phenanthridin-6-one derivatives. Aza-ortho-xylylene 16 generated from 3,3-diallylbenzosultam 15 transforms into arylcyclohexadiene 19, which finally adds NPMI to form bicyclo[2.2.2]octene derivative 20.
EN
Reactions of 1,4-naphthoquinone with aza-ortho-xylylenes generated via thermal extrusion of SO2 from 2,1-benzisothiazoline 2,2-dioxides (benzosultams) lead to tetrahydronaphthalene-2-spiro-2'-dihydroindole derivatives. Aza-ortho-xylylene generated via thermal ring opening of 1-phenylbenzazetidine gave with naphthoquinone benzo[b]acridine deritative 15.
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