Synthesis and halogenation of propargyl pyrazolo-[3,4-d]pyrimidine thioether

Onysko, M. Yu.; Svalyavin, O. V.; Туров, А. В.; Lendel, V. G.

doi:10.1007/s10593-008-0123-4

Cited by 10 publications

(7 citation statements)

References 1 publication

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…It is noteworthy that the halogenation of 2-(propargylthio)pyrimidin-4-ones 11 22,23 and 4-imino(oxo)-6-propargylthio(amino)pyrazolo [3,4-d]pyrimidines 12 [24][25][26] nonstereoselectively gives the similar angular condensed heterocyclic system 14, albeit the Z-isomer dominates in the reaction mixture (Scheme 3). The use of the sulfuric acid as the electrophile leads to protonation of the more basic nitrogen atom with the formation of linearly fused pyrimidines 15 from thioethers, 25 or angular condensed systems 16 from amino derivatives, 26 whereas HBr only protonates the heterocyclic nitrogen with retention of the triple bond.…”

Section: Short Review Synthesismentioning

confidence: 99%

“…It is remarkable that the regiochemistry of these electrophilic cyclizations is virtually independent of the solvents and conditions, whereas the nature of the unsaturated moiety has a major impact on the direction of the electrophilic cyclization (Scheme 5). Alkenylsulfanyl(amino)substituted pyrido [2,3-d]( [3,4-d])pyrimidin-4(3H)-ones, [28][29][30] pteridin-4(3H)-one, 31 pyrimidin-4(5H)-ones, 22,23,27,[32][33][34] thieno [2,3-d]pyrimidin-4(3H)-ones, 35 and pyrazolo [3,4d]pyrimidines [24][25][26]36 22 were used as the starting materials. Glacial acetic or chloroform at room temperature were used as typical solvents for the halogenation, whilst nitromethane with LiClO 4 as an additive were used for arylsulfenyl chlorination.…”

Section: Short Review Synthesismentioning

confidence: 99%

See 1 more Smart Citation

The Use of Electrophilic Cyclization for the Preparation of Condensed Heterocycles

Slivka¹,

Onysko²

2021

Synthesis

View full text Add to dashboard Cite

Condensed heterocycles are well-known for their excellent biological effects and they are undeniably important compounds in organic chemistry. Electrophilic cyclization reactions are widely used for the synthesis of mono-heterocyclic compounds. This review highlights the utility of electrophilic cyclization reactions as an effective generic tool for the synthesis of various condensed heterocycles containing functional groups that are able to undergo further chemical transformations, such as nucleophilic substitution, elimination, re-cyclization, cleavage, etc. This review describes the reactions of unsaturated derivatives of different heterocycles with various electrophilic agents (halogens, arylsulfanyl chlorides, mineral acids) resulting in annulation of an additional partially saturated heterocycle. The electrophilic reaction conditions, plausible mechanisms and the use of such transformations in organic synthesis are also discussed. The review mainly focuses on research published since 2002 in order to establish the current state of the art in this area. 1 Introduction2 Electrophilic Cyclization Pathways Involving a Nitrogen Nucleophilic Center3 Electrophilic Cyclization Pathways Involving a Chalcogen Nucleophilic Center3.1 Sulfur Centers3.2 Oxygen Centers3.3 Selenium Centers4 Strategies and Mechanisms5 Conclusion

show abstract

Section: Short Review Synthesismentioning

confidence: 99%

Section: Short Review Synthesismentioning

confidence: 99%

The Use of Electrophilic Cyclization for the Preparation of Condensed Heterocycles

Slivka¹,

Onysko²

2021

Synthesis

View full text Add to dashboard Cite

show abstract

“…On the other hand, the halogens are convenient electrophilic reagents, which are widely used in heterocyclic chemistry [15–19]. In our previous work, we have established that electrophilic halogencyclization of terminally unsubstituted alkenyl (thio‐)ethers of fused heteroarylpyrimidinones results in the annulation of the thiazoline ring [20–26]. There are interesting features associated with the hindered rotation of aromatic substituent in the NMR spectra of condensed pyrazolothiazolopyrimidinium trihalides containing phenyl substituent at the heterocyclic nitrogen [22], which result to the chemical shifts of all the magnetic nuclei of the phenyl residue becoming anisochronous.…”

Section: Introductionmentioning

confidence: 99%

Highly efficient synthesis and NMR features of novel fused pyrimidothiazinium trihalogenides

Onysko

Svalyavin

Slivka

et al. 2021

Journal of Heterocyclic Chem

View full text Add to dashboard Cite

Condensed pyrimidines are a popular class of heterocyclic compounds because they have a wide range of biological activity. This article aims to evaluate the simple, catalyst‐free procedure of synthesis of novel fused pyrimidothiazines. An efficient access to a series of pyrazolo[4′,3′:5,6]pyrimido[2,1‐b][1,3]thiazinium, pyrazolo[3′,4′:5,6]pyrimido[2,1‐b][1,3]‐thiazinium, and benzo[b]thieno[4′,3′:5,6]pyrimido[2,1‐b][1,3]thiazinium trihalogenides was developed via electrophilic heterocyclization of corresponding pyrimidine cinnamyl thioethers under the action of halogens. The XDR and complex NMR investigations were used for solving of final products structure; the anisochronism was observed in the NMR spectra of synthesized compounds for the pairs of ortho‐ and meta‐protons, as well as the N‐phenyl substituents associated with them.

show abstract

“…Reactions of electrophilic heterocyclization are widely used for the synthesis of various heterocyclic polycyclic systems . Some resources describe the impact of different factors (the nature of the electrophilic reagent, the polarization of the alkenyl substituent, the nucleophilicity of the exo‐heteroatom or endocyclic heteroatom, the nature of the condensed ring, and the reaction conditions) on the regiochemistry of the process of electrophilic intramolecular cyclization of alkenyl derivatives of heterocycles .…”

Section: Introductionmentioning

confidence: 99%

The Influence of Condensed Cycle on Regiochemistry of Electrophilic Heterocyclization of 3‐Alkenyl‐2‐Thioxopyrimidin‐4‐One by p‐Alkoxyphenyltellurium Trichloride

Kut

Onysko

Lendel

2018

Journal of Heterocyclic Chem

View full text Add to dashboard Cite

in Wiley Online Library (wileyonlinelibrary.com).Electrophilic heterocyclization of 5-alkenyl-1-methyl-6-thioxopyrazolo [3,4-d]pyrimidin-4-ones and 3alkenyl-2-thioxoquinazoline-4-ones under the action of p-alkoxyphenyltellurium trichloride leads to annulation of thiazoline cycle with formation of 7-[(p-alkoxyphenyl)telluromethyl]-1-methyl-6,7dihydropyrazolo[3,4-d][1,3]thiazolo[3,2-a]pyrimidin-4(1H)-ones hydrochlorides and 2-(p-alkoxyphenyl) dichlorotelluromethyl-2,3-dihydro-5H-[1,3]thiazolo[2,3-b]quinazolin-5-ones hydrochlorides. Reduction of salts by the action of excess of sodium sulfite leads to formation of arylhetaryl telluride. in 20 mL of triethylamine. The reaction mixture was refluxed for 2 h. Precipitate was filtered and washed by methanol. The product was crystalized from ethanol. 3-Prop-2-en-1-yl-2-thioxo-2,3-dihydroquinazolin-4(1H)-one(6). Yield 61%; white powder (ethanol); mp. 203-205°C; mp. 201°C [18]; IR (KBr): (v/см À1 ) = 1648 (C═O); 1 H NMR (400 MHz, DMSO-d 6 ): δ (ppm) 12.94 (s, 1H), 7.92 (d, J = 8.0 Hz, 1H), 7.72 (t, J = 7.8 Hz, 1H), 7.39 (d, J = 8.4 Hz, 1H), 7.31 (t, J = 7.6 Hz, 1H), 5.90 (m, 1H), 5.15 (dd, J = 5.2, 1.2 Hz, 1H), 5.12 (d, J = 1.6, Hz 1H), 5.03 (d, J = 3.6 Hz, 2H). 13 С NMR: δ (ppm) 3-(2-Methylprop-2-en-1-yl)-2-thioxo-2,3-dihydroquinazolin-4(1H)-one (7). Yield 61%; white powder (ethanol); mp. 212-214°C. IR (KBr): (v/см À1 ) = 1655 (С═О); 1 H NMR (400 MHz, DMSO-d 6 ) δ (ppm) 12.93 (s, 1H), 7.95 (d, J = 7.2 Hz, 1H), 7.75 (t, J = 7.6 Hz, 1H), 7.37 (d, J = 8.4 Hz, 1H), 7.34 (t, J = 7.6 Hz, 1H), 4.92 (s, 2H), 4.72 (s, 1H), 4.46 (s, 1H), 1.73 (s, 3H). 13 С NMR: δ General procedure for the preparation of 7-(pmethoxyphenyl)dichlorotelluromethyl-2,3-dihydro-5H-[1,3] thiazolo[2,3-b]quinazolin-5-ones hydrochlorides. The 1 mmol of 3-alkenyl-2-thioxo-2,3-dihydroquinazolin-4(1H)-one 6 or 7, dissolved in 20 mL of acetic acid, was added to 1 mmol of p-alkoxyphenyltellutium trichloride in 20 mL of acetic acid. The reaction mixture was stirring at room temperature for 8 h. Target product was filtered and recrystallized from acetic acid. 3-[Dichloro(4-methoxyphenyl)telluromethyl]-2,3-dihydro-5H-[1,3]thiazolo[2,3-b]quinazolin-5-one hydrochloride (8). Yield55%; white powder (acetic acid); mp. 143-145°C; IR (KBr): (v/см À1 ) = 1690 (С═О); 1 H NMR (400 MHz, DMSO-d 6 ) δ (ppm) 8.07 (d, J = 8.0 Hz, 1H), 8.05 (d, J = 7.2 Hz, 2H), 7.78 (t, J = 7.6 Hz, 1H), 7.55 (d, J = 8.4 Hz, 1H), 7.46 (t, J = 8 Hz, 1H), 7.55 (d, J = 8.4 Hz, 1H), 7.08 (d, J = 7.2 Hz, 1H), 4.76 (m, 1H), 4.67 (d, J = 13.2 Hz, 1H), 4.44 (dd, J = 12.8, 7.2 Hz, 1H), April 2018Regiochemistry of Electrophilic Heterocyclization of 3-Alkenyl-2-Thioxopyrimidin-4-One by p-Alkoxyphenyltellurium Trichloride

show abstract

Synthesis and halogenation of propargyl pyrazolo-[3,4-d]pyrimidine thioether

Cited by 10 publications

References 1 publication

The Use of Electrophilic Cyclization for the Preparation of Condensed Heterocycles

The Use of Electrophilic Cyclization for the Preparation of Condensed Heterocycles

Highly efficient synthesis and NMR features of novel fused pyrimidothiazinium trihalogenides

The Influence of Condensed Cycle on Regiochemistry of Electrophilic Heterocyclization of 3‐Alkenyl‐2‐Thioxopyrimidin‐4‐One by p‐Alkoxyphenyltellurium Trichloride

Contact Info

Product

Resources

About