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1

Thermal [3+2] cycloaddition reactions as most universal way for the effective preparation of five-membered nitrogen containing heterocycles

Kras Jowita, Sadowski Mikołaj, Zawadzińska Karolina, Nagatsky Roman, Woliński Przemysław, Kula Karolina, Łapczuk Agnieszka

Scientiae Radices

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2023

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Vol. 2, Iss. 3

247--267

EN

The possibility of the construction of five-membered heterocycles, including single heteroatom or systems with two, three and four heteroatoms were critically reviewed based on the recent reports regarding to the [3+2] cycloaddition reactions. Almost all of analysed reaction are realized with high regio- and stereoselectivity.

2

Chemiczna synteza soli amoniowych acetamiprydu, badania spektroskopowe ich równowagowych struktur izomerycznych i ich aktywności grzybobójczej

Maranda Andrzej, Schilf Wojciech, Gucma Mirosław, Gołębiewski Wiesław Marek, Krawczyk Maria, Pucko Wiesław

Przemysł Chemiczny

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2023

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T. 102, nr 5

438--467

PL

Osiem nieznanych amoniowych soli acetamiprydu (I) (acetamipridium) (chlorowodorek, siarczan, ortofosforan, mrówczan, chlorooctan, trichlorooctan, metanosulfonian i kakodylan) zsyntetyzowano przez wieloetapową konwersję 3-metylopirydyny i zbadano pod kątem struktur równowagowych w solach za pomocą spektroskopii 2D-NMR i widm NOESY w celu wykazania istnienia 2 różnych struktur izomerycznych I (stosunek 80/20). Dla porównania zsyntetyzowano i zidentyfikowano 8 nieznanych analogicznych soli 3-metylopirydyny. Analizę rentgenowską rosnących kryształów I wykorzystano do identyfikacji izomerii geometrycznej cis/trans grup Me w I oraz do potwierdzenia jej struktury. Widma korelacyjne HMBC(¹⁵N-¹H) NMR z powodzeniem wykorzystano do zlokalizowania atomów N w badanych solach I, w których doszło do protonowania. Wykazano również działanie grzybobójcze struktury trans-I.

EN

Eight unknown acetamiprid (I) ammonium (acetamipridium) salts (hydrochloride, sulfate, orthophosphate, formate, chloroacetate, trichloroacetate, methanesulfonate, and cacodilate) were synthesized by multi-stage conversion of 3-methylpyridine and studied for isomeric equil. in solns. by 2D-NMR spectroscopy and NOESY spectra to evidence the existence of 2 different isomeric structures of I (ratio 80/20). For comparison, 8 unknown analogous 3-methylpyridine salts were synthesized and identified. The X-ray anal. of growing I crystals was used to identify the geometric cis/trans isomerism of Me groups in I and to confirm its structure. The HMBC (15N-1H) NMR correlation spectra were successfully used to localize the N atoms in studied I salts where protonation took place. The fungicidal activity of the trans-I structure was also evidenced.

3

Reakcje [2+3] cykloaddycji sprzężonych nitro alkenów w świetle teorii indeksów elektrofilowości

Dresler E., Jasińska E., Nowakowska-Bogdan E., Jasiński R.

Chemik

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2015

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Vol. 69, nr 3

146--153

PL

W pracy – na podstawie danych literaturowych – przedyskutowano możliwość wykorzystania indeksów elektrofilowości do interpretowania przebiegu polarnych [2+3] cykloaddycji. Dyskusję tę przeprowadzono w odniesieniu do reakcji z udziałem sprzężonych nitroalkenów.

EN

In the publication – on the basis of the published literature – the possibility of using electrophilicity indexes for interpretation of the course of the polar [2+3] cycloaddition reactions has been discussed. The analysis is referring to the coupled reaction involving nitroalkenes.

4

Regio- i stereoselektywność [2+3] cykloaddycji α-podstawionych nitroetenów z 1,3-dipolami propargilo-allenowego i allilowego typu

Jasiński R., Mikulska M., Socha J., Barański A.

Czasopismo Techniczne. Chemia

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2012

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R. 109, z. 2-Ch

53--63

PL

W artykule przeprowadzono krytyczną analizę danych literaturowych dotyczących regioi stereoselektywności reakcji [2+3] cykloaddycji z udziałem α-podstawionych nitroetenów.

EN

The paper is a critical review of available literature data about regio- and stereoselectivity of [2+3] cycloaddition reactions of α-substituted nitroethenes.

5

Enzymatyczne utlenianie typu Baeyera-Villgera

Kołek T., Świzdor A., Panek A.

Wiadomości Chemiczne

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2009

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[Z] 63, 9-10

819-845

EN

Baeyer-Villiger (BV) reaction is oxidation of ketones, leading to cleavage of one of the C-CO-C bonds with simultaneous insertion of an oxygen atom into the cleaved bond. Resulting products obtained from cyclic ketones are lactones, while esters are obtained from acyclic ketones. Numerous strains of microorganisms produce enzymes catalyzing BV oxidation. These enzymes participate in the processes of degradation of natural and synthetic ketones, which can be used by the microorganisms as carbon source (Scheme 3 and 4). The enzymes are monooxygenases (Baeyer-Villigerases, BVMOs), usually containing flavinoadenine nucleotide and cooperating with NAD(P)H reductases. Research on the role of BV oxidation in degradation processes has evolved into intensive studies on the mechanism of this reaction and its use in synthesis, especially after isolation (in 1976) of cyclohexane monooxygenase from Acinetobacter sp. NCIB9871(CHMOAcineto 1) [9]. Subsequently, further strains were identified which produced BVMOs catalyzing oxidation of ketones of diverse structures. In addition to the best-characterized cyclohexane monooxygenase, there are: cyclopentanone, phenylacetone, cyclododecanone, aliphatic ketone and 2-oxo-3-en-4,5,5-trimethyl-cyclopentenylacetic acid monooxygenases. The adjective characterizing a given BVMO is derived from the ketone constituting carbon source, or from the ketone which is oxidized with the highest yield. In addition to these ketones, the enzymes accept their various structural analogues, therefore it is possible to select a biocatalyst which carries out oxidation of a given substrate. Among BVMOs, particularly selective are the enzymes carrying out BV oxidation of steroidal ketones: these enzymes operate only on steroid substrates, mostly containing 3-oxo--4-en moiety, but also they exhibit regioselectivity as well - the oxidation of ketones takes place only at C-17. During the regioselective enzymatic oxidation, "atypical" lactones [2, 4], which are not produced in chemical BV oxidation processes, are sometimes formed. Products of stereoselective enzymatic reactions are optically pure lactones and esters, which are starting points for further asymmetric synthesis of biologically active compounds, including medicines. The application of genetic engineering allows obtaining recombinant microbial strains, which are non-pathogenic and produce larger amounts of the enzyme than the wild-type strains. The recombinants are also able to produce mutated BVMOs exhibiting higher selectivity and/or lifetime, as well as activity towards different spectrum of substrates than the parent enzymes [2]. However, reaction yields of transformations carried out by the recombinants are still not significantly better than the results obtained with the wild-type strains. The recombinants usually require an expensive reagent, isopropyl-? --D-tiogalactopyranoside (ITPG), to induce their BVMOs [23]. Enzymatic BV oxidation, due to the selectivity of the enzymatic action, is competitive to the chemical oxidation. The enzyme selectivity allows for using pure products, including enantiopure compounds, with high yield. The process is environmentally friendly, because the oxidizer in the enzymatic BV reaction is molecular oxygen, and the amount of byproducts is limited. Synthetic application of BVMOs is limited by three principal factors: isolation of the enzyme in amounts suitable for large-scale applications, decrease in the enzymatic activity in the presence of the substrate and/or the product, and the isolation of the product. Separation of the unreacted enantiomer of the substrate in the process of kinetic separation of the racemic mixture, or separation of regioisomeric lactones are costly and time-consuming operations. Another possible problem is the fact that some strains producing useful BVMOs are pathogenic. Therefore, multidirectional research efforts are devoted to overcome the aforementioned barriers with the goal of establishing economically viable methods of biotransformations [4].

6

Regionoselektywność [2+3] cykloaddycji nitroetenu z Z-C,N-diarylonitronami w świetle teorii FMO

Jasiński R., Mikulska M., Pawlik H., Barański A.

Czasopismo Techniczne. Mechanika

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2008

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R. 105, z. 2-M

121-127

PL

Na podstawie danych obliczeń kwantowochemicznych przeprowadzono analizę pierwotnych efektów orbitalnych oraz coulombowskich w reakcjach [2+3] cykloaddycji diarylonitronów z nitroetenem. Ustalono, że efekty te generalnie sprzyjają powstawaniu odpowiednich 4-nitroizoksazolidyn.

EN

Using quantum-chemical calculations we have carried out an analysis of frontier molecular orbital interactions in the [2+3] cycloaddition reactions of nitroethene with diarylnitrones. In all cases the primary orbital effects and coulombic interactions favored the corresponding 4-nitroisoxazolidines.

7

Peri- i regioselektywność cykloprzyłączenia nitroetenu do Z-C-antranilo-N-arylonitronów w świetle teorii FMO

Pawlik H., Jasiński R., Barański A.

Czasopismo Techniczne. Chemia

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2008

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R. 105, z. 1-Ch

93-99

PL

Na podstawie danych obliczeń AM1 przedyskutowano charakter pierwotnych efektów orbitalnych cykloprzyłączenia Z-C-antranilo-N-arylonitronów do nitroetenu. Ustalono, że efekty te powinny sprzyjać konwersji reagentów wg mechanizmu [2+4] cykloaddycji.

EN

Using data of AM1 calculations we carried out discussion about character of FMO interaction in cycloadditions of Z-C-anthranil-N-arylonitrones to nitroethene. In all cases that effects should favored conversion of reagents in [2+4] mechanism of cycloaddition.

8

Effect of Base and Acyl Chloride on Regioselectivity of Acylation of 8,8-Pentamethylene-2-methyl-7,9-dioxa-1-azaspiro[4.5]dec-1-ene 1-Oxide

Koszytkowska-Stawińska M., Gębarowski P., Sas W.

Polish Journal of Chemistry

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2004

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Vol. 78 / nr 2

217-222

EN

Acylation of 2-methyl-7,9-dioxa-1-azaspiro[4.5]dec-1-ene 1-oxide (5) in the presence of pyridine gives 3-acyloxy-2-methyl-1-pyrroline derivatives 6 independently of kind of acid chloride, while treatment of 5 with benzoyl or p-nitrobenzoyl chloride and triethylamine affords mainly 2-benzoyloxymethyl- 8a and 2-p-nitrobenzoyloxymethyl-1-pyrroline 8b, respectively. Acetylation of 5 was base-independent.

9

Synthesis and Properties of Azoles and Their Derivatives : XLIII. Regio- and Stereoselectivity of [2+3] Cycloaddition Reaction of E-B-Nitrostyrene to Z-C-Aryl-N-phenylnitrones

Barański A.

Polish Journal of Chemistry

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2000

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Vol. 74, nr 6

767-775

EN

E-B-Nitrostyrene (1) reacts with Z-C-acryl- N-phenylnitrones (2a-h) exclusively to give trans- and cis-2,5-diphenyl-3-aryl-4-nitroisoxazolidines (3a-h, 4a-h) in high yield. The molar ratio of trans and cis stereoisomers is affected by substituent in phenyl ring of the parent nitrone (2c). The reaction is found by AM1 calculations to be controlled bt the interactions of the HOMO of nitrone with the LUMO of nitrostyrene.