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1

The participation of oleic acid and its esters in [3+2] cycloaddition reactions: a mini-review

Dresler Ewa

Scientiae Radices

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2024

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Vol. 3, Iss. 1

53--61

EN

This mini review presents the state of knowledge on the [3+2] cycloaddition reactions involving fatty acids and their esters with triatomic components (TAC). In general, the literature reports are quite sparse and relatively old. The reaction yield was in the range of 12-85%. The best result of 32CA was obtained from the reaction of butylonitrile N-oxide (4) and methyl oleate (2). Other tested TAC as components of title reactions were nitrylimines and ozone.

2

Unusual regioselectivity in [3+2] cycloaddition reactions between (E)-3-nitroacrylic acid derivatives and (Z)-C,N-diphenylimine N-oxide

Kras Jowita, Wróblewska Aneta, Kącka-Zych Agnieszka

Scientiae Radices

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2023

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Vol. 2, Iss. 2

112-117

EN

[3+2] cycloaddition reactions of -COOMe and -CN trans-substituted nitroethenes with (Z)-C,N-diphenylimine N-oxide were tested. For the contrast to most known nitroalkene/nitrone cycloaditions, the reactions studied realized with the formation of 5-nitroisoxazolidines.

3

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.

4

The extraordinary gravity of three atom 4π-components and 1,3-dienes to C20-nXn fullerenes; a new gate to the future of Nano technology

Siadati Seyyed Amir, Rezazadeh Solmaz

Scientiae Radices

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2022

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Vol. 1, Iss. 1

46--68

EN

A quick glance to the adsorption, sensing, and energy storage abilities of C₂₀ fullerene and its derivatives indicate that this small carbon cluster may have extraordinary properties which would make it a key part of the future of Nano actuators and Nano machines. For example, in the case of the gravity of three atom 4π-components (TACs) to these carbon cages, it should be noted that; the rate constants (K)s of the reaction of C₂₀ fullerene with 1,3-butadiene (Diels-Alder (DA) process), and with 2-furan nitrile oxide ([3+2] cycloaddition (32CA process)) are 2.51(10¹¹) M^-1 s^-1, and 1.4(10⁷) M^-1s^-1, respectively. However, the rate constant of the 32CAreaction between norbornadiene and 3,4-dihydro isoquinoline-N-oxide is about 2.56(10) M^-1 s^-1 (both by DFT and by experimental results). This simple comparison could show the extraordinary gravity of some TACs and dienes to C₂₀ fullerenes.

5

Polar [3+2] cycloaddition between N-methyl azomethine ylide and trans-3,3,3-trichloro-1-nitroprop-1-ene

Żmigrodzka Magdalena, Sadowski Mikołaj, Kras Jowita, Dresler Ewa, Demchuk Oleg M., Kula Karolina

Scientiae Radices

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2022

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Vol. 1, Iss. 1

26--35

EN

Pyrrolidines are important heterocyclic organic compounds which show biological effects. Many of them are successfully used in medicine. These compounds can also be applied in industry, for example as dyes or agrochemical substances. Therefore, the study of pyrrolidines chemistry is important for modern science. In this paper the pyrrolidines synthesis in [3+2] cycloaddition between Nmethyl azomethine ylide and trans-3,3,3-trichloro-1-nitroprop-1-ene was studied. The reaction was carried out experimentally and based on computational research. The obtained results show the reaction may be of a polar nature, and proceed under mild conditions leading to (3SR,4RS)-1-methyl-3-nitro-4-(trichloromethyl)pyrrolidine as a single reaction product. Probably, a similar protocol can be applied for analogous reactions involving other 2-substituted nitroethene analogues.

6

Trihalogenonitropropeny w reakcjach [4+2]-π-elektronowych cykloaddycji

Szczepanek A., Mróz K., Goliasz G., Jasiński R.

Chemik

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2011

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Vol. 65, nr 10

1049-1054

PL

W pracy przeprowadzono krytyczną analizę danych literaturowych dotyczących reakcji [3+2] i [4+2] cykloaddycji z udziałem trihalogenonitropropenów.

EN

The work is a critical review of available literature data concerning the reaction of [3+2] and [4+2] cycloaddition reactions of trihalonitropropenes.

7

Quantum chemical calculations on S-centered 1,3-dipoles : 2. Reactivity of thiocarbonyl S-imides in perycyclic reactions

Mlostoń G., Fabian J.

Polish Journal of Chemistry

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1999

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vol. 73 nr 4

683-692

EN

Results of high level quantum chemical calculations on thiocarbonyl S-imides 1 are reported. The reactivity of thioformaldehyde S-imide (1a) (CH2S+NH-) in pericyclic reactions was calculated by density functional theory using gradient corrected functionals in conjunction with 6-31+G(d,p) and 6-31+G(3df, 3dp) basis sets. For the sake of comparison, conventional ab initio quantum chemical calculations at correlated levels of theory, such as MP2, QCISD(T) G1 and G2(MP2), were also performed. The predicted reactivity of the parent compound is compared with those of some closely related ylides (S-centered 1,3-dipoles), such as thioformaldehyde S-methylide (2a), thioformaldehyde S- oxide (3a) and thioformaldehyde S-sulfide (4a). To show the effect of substitution on structure and reactivity a series of acyclic and cyclic substituted thiocarbonyl S-imides 1b-k was calculated. The 1,3-electrocyclic ring closure of 1a to form thiaziridines 5 is predicted to be exothermic process by about 10 kcal/mol with activation energies of about 30 kcal/mol. The calculated reaction energies are considerably affected by higher angular momentum polarization functions, such as f-functions. In the case of some substituted thiocarbonyl S-imides, such as thiotropone S-imide (1i) and thiofluorenone S-imide (1j), the exothermicity of the ring closure reaction is lower than that of the parent compound. The concerted prototype [3+2]-cycloaddition of 1a with ethylene is strongly exothermic (about 50 kcal/mol) with the activation energy of about 20 kcal/mol. The energetics of both types of the pericyclic reactions of 1a appears closely related to that of 4a but differs more strongly from that of 3a. The contemporary knowledge on thiocarbonyl S-imides 1 is reviewed and discussed in conjunction with theoretical results.