scholarly journals Phosphorylation of glycoluryl derivatives with phosphorus pentachloride

2021 ◽  
Vol 101 (1) ◽  
pp. 12-18
Author(s):  
L.K. Salkeeva ◽  
◽  
A.A. Muratbekova ◽  
E.V. Minayeva ◽  
P. Voitichek ◽  
...  
Keyword(s):  
Room Temperature ◽  
Phosphorus Pentachloride ◽  
Reaction Centers ◽  
Phosphorus Trichloride ◽  
Crystalline Substance ◽  
Prolonged Heating ◽  
Pentavalent Phosphorus ◽  
Reaction Proceeds ◽  
Derivatives Of ◽  
Effective Reaction

The paperpresents the research results on the synthesis and study of new organophosphorus derivatives of glycoluril, obtained on the basis of pentavalent phosphorus. New organoelement phosphorus derivatives synthesized on the basis of N-acyl-substituted glycolurilhave been obtained.They are of considerable interest due to the presence of effective reaction centers. Tetraacetyl-substituted glycoluril —2,4,6,8-tetraacetyl-2,4,6,8-tetraazabicyclo[3,3,0]octane-3,7-dione was chosen as theinitial synthon. Theuse of unsubstituted glycoluril in the reaction of direct phosphorylation by the action of phosphorus trichloride or pentachloride is not possible due to the absence of active phosphorylation centers. It was experimentally shown that the reaction proceeds with prolonged heating for at least 48 hours in an argon. Theinitial acyl derivative of glycoluril and phosphorus pentachloride in theratio of 1:6 and leads to the formation of diphosphonic complex of tetraacetylglycoluril —dihexachlorophosphorate 2,6-diacetyl-(4,8-diacetyl-2,4,6,8-tetraaza-bicyclo[3.3.0]octane-3,7-dione)-2,6-di(chloroethenyltrichlorophosphonium). The obtained compoundis a white crystalline substance unstable in air. Decomposition of the diphosphonic complex was carried out using benzaldehyde and proceeds with the formation of the corresponding dichlorophosphate derivative, also unstable in air and rapidly decomposing at room temperature.

Solvent-assisted osmium staining of butyl acrylate and ethylene-propylene-diene in a styrene acrylonitrile matrix

1993 ◽  
Vol 51 ◽  
pp. 900-901 ◽  
Author(s):  
Gudrun A. Hutchins
Keyword(s):  
Butyl Acrylate ◽  
Room Temperature ◽  
Osmium Tetroxide ◽  
Staining Procedure ◽  
Reactive Site ◽  
Ethylene Propylene ◽  
Minimal Distortion ◽  
Styrene Acrylonitrile ◽  
Engineering Polymers ◽  
Effective Reaction

In order to optimize the toughening effect of elastomers in engineering polymers, it is necessary to characterize the size, morphology and dispersion of the specific elastomer within the polymer matrix. For unsaturated elastomers such as butadiene or isoprene, staining with osmium tetroxide is a well established procedure. The residual carbon-carbon double bond in these materials is the reactive site and forms a 1,2-dilato complex with the OsO4. Incorporation of osmium tetroxide into the elastomer not only produces sufficient contrast for TEM, but also crosslinks the elastomer sufficiently so that ultramicrotomy can be accomplished at room temperature with minimal distortion.Blends containing saturated elastomers such as butyl acrylate (BA) and ethylene propylene diene monomer (EPDM) cannot be stained directly with OsO4 because effective reaction sites such as C=C or -NH2 are not available in sufficient number. If additional reaction sites can be introduced selectively into the elastomer by a chemical reaction or the absorption of a solvent, a modified, two-step osmium staining procedure is possible.

Development of the room temperature protocol based on room temperature ionic liquids and surfactant ionic liquids for the synthesis of derivatives of 2-amino-thiazoles and thermo-physical analysis of the synthesized derivatives using TGA-DSC.

2020 ◽  
Vol 10 ◽  
Author(s):  
Chandrakant Sarode ◽  
Sachin Yeole ◽  
Ganesh Chaudhari ◽  
Govinda Waghulde ◽  
Gaurav Gupta
Keyword(s):  
Thermal Analysis ◽  
Heat Capacity ◽  
Ionic Liquids ◽  
Specific Heat ◽  
Specific Heat Capacity ◽  
Room Temperature ◽  
Heat Capacity Data ◽  
General Strategy ◽  
Capacity Data ◽  
Derivatives Of

Aims: To develop an efficient protocol, which involves an elegant exploration of the catalytic potential of both the room temperature and surfactant ionic liquids towards the synthesis of biologically important derivatives of 2-aminothiazole. Objective: Specific heat capacity data as a function of temperature for the synthesized 2- aminothiazole derivatives has been advanced by exploring their thermal profiles. Method: The thermal gravimetry analysis and differential scanning calorimetry techniques are used systematically. Results: The present strategy could prove to be a useful general strategy for researchers working in the field of surfactants and surfactant based ionic liquids towards their exploration in organic synthesis. In addition to that, effect of electronic parameters on the melting temperature of the corresponding 2-aminothiazole has been demonstrated with the help of thermal analysis. Specific heat capacity data as a function of temperature for the synthesized 2-aminothiazole derivatives has also been reported. Conclusion: Melting behavior of the synthesized 2-aminothiazole derivatives is to be described on the basis of electronic effects with the help of thermal analysis. Additionally, the specific heat capacity data can be helpful to the chemists, those are engaged in chemical modelling as well as docking studies. Furthermore, the data also helps to determine valuable thermodynamic parameters such as entropy and enthalpy.

scholarly journals The Three-Component Synthesis of 4-Sulfonyl-1,2,3-triazoles via a Sequential Aerobic Copper-Catalyzed Sulfonylation and Dimroth Cyclization

Molecules ◽  
2021 ◽  
Vol 26 (3) ◽  
pp. 581
Author(s):  
Max Van Hoof ◽  
Santhini Pulikkal Veettil ◽  
Wim Dehaen
Keyword(s):  
Room Temperature ◽  
Aromatic Ketones ◽  
Three Component Reaction ◽  
Reaction Proceeds

4-Sulfonyl-1,2,3-triazole scaffolds possess promising bioactivities and applications as anion binders. However, these structures remain relatively unexplored and efficient synthetic procedures for their synthesis remain desirable. A practical room-temperature, aerobic copper-catalyzed three-component reaction of aromatic ketones, sodium sulfinates, and azides is reported. This procedure allows for facile access to 4-sulfonyl-1,5-disubstituted-1,2,3-triazoles in yields ranging from 34 to 89%. The reaction proceeds via a sequential aerobic copper(II)chloride-catalyzed oxidative sulfonylation and the Dimroth azide–enolate cycloaddition.

Alkene Difunctionalization Directed by Free Amines: Diamine Synthesis via Nickel-Catalyzed 1,2-Carboamination

2021 ◽  
Author(s):  
Taeho Kang ◽  
José Manuel González ◽  
Zi-Qi Li ◽  
Klement Foo ◽  
Peter Cheng ◽  
...  
Keyword(s):  
Nickel Catalyst ◽  
Room Temperature ◽  
Kinetic Studies ◽  
Fine Tuning ◽  
Secondary Amines ◽  
Protecting Group ◽  
Wide Range ◽  
Leaving Group ◽  
Primary And Secondary Amines ◽  
Reaction Proceeds

A versatile method to access differentially substituted 1,3- and 1,4-diamines via a nickel-catalyzed three-component 1,2-carboamination of alkenyl amines with aryl/alkenylboronic ester nucleophiles and N–O electrophiles is reported. The reaction proceeds efficiently with free primary and secondary amines without needing a directing auxiliary or protecting group, and is enabled by fine-tuning the leaving group on the N–O reagent. The transformation is highly regioselective and compatible with a wide range of coupling partners and alkenyl amine substrates, all performed at room temperature. A series of kinetic studies support a mechanism in which alkene coordination to the nickel catalyst is turnover-limiting.

Cleavage Reactions of 5-Arylazo Derivatives of 1-Methyl-2-benzyl-2-imidazolin-4-ones

1975 ◽  
Vol 30 (7-8) ◽  
pp. 603-605 ◽  
Author(s):  
Nazmi Abdel Latif Kassab ◽  
Abdel Hamid Harhash ◽  
Sanna Osman Abd Allah
Keyword(s):  
Sodium Hydroxide Solution ◽  
Aqueous Sodium Hydroxide ◽  
The Other ◽  
Ring Cleavage ◽  
Prolonged Heating ◽  
Aqueous Sodium Hydroxide Solution ◽  
Aqueous Sodium ◽  
Triazine Derivatives ◽  
Cleavage Reactions ◽  
Derivatives Of

The 5-arylazo-1-methyl-2-benzyl-2-imidazolin-4-ones (1 a-c) undergo ring cleavage with 1% aqueous sodium hydroxide solution affording α-arylhydrazono-phenacetyl-sarcosine amide (2). Prolonged heating of 1 and 2 with the same reagent yields the cyanamide (3). On the other hand, when 1 a-c were refluxed with acetic acid the triazinones (4) were obtained. The latter adds one mole of Grignards reagent to yield the 5-hydroxy-1,2,4-triazine derivatives (5).

scholarly journals CHEMISTRY AND SYNTHESIS OF SOME DIHYDRO-2H-l,4-BENZOTHIAZINE DERIVATIVES

1966 ◽  
Vol 44 (11) ◽  
pp. 1247-1258 ◽  
Author(s):  
Raj Nandan Prasad ◽  
Karin Tietje
Keyword(s):  
Alkyl Halides ◽  
Reduction Product ◽  
Alkyl Derivatives ◽  
Reaction Proceeds ◽  
Thiazine Ring ◽  
Derivatives Of ◽  
Compound Xviii ◽  
Acyl Derivatives

The formation of 3-oxo-3,4-dihydro-2H-1,4-benzothiazine (IIIa) by cyclization of alkyl 2-haloacetamidophenyl sulfides (I) was investigated; it is proposed that the reaction proceeds via a six-membered sulfonium halide. The preparation of 4-alkyl derivatives of IIIa and of 4-alkyl and 4-acyl derivatives of its reduction product 3,4-dihydro-2H-1,4-benzothiazine (Va) is described. Acylation of Va was shown to proceed without opening of the thiazine ring. Preparation of the O-benzoyl, N-benzoyl, and O,N-dibenzoyl derivatives of 2-(β-hydroxyethyl-mercapto)aniline (VIII) has permitted clarification of the confusion in the literature with respect to the derivatives of Va and VIII. Compound XVIII, the 1,1-dioxide of IIIa, undergoes C-alkylation at the 2-position when treated with alkyl halides, rather than O-alkylation as previously suggested.

scholarly journals Enantioenriched Quaternary α-Pentafluoroethyl Derivatives of Alkyl 1-Indanone-2-Carboxylates

2020 ◽  
Author(s):  
Albert Granados ◽  
Anna Balleteros ◽  
Adelina Vallribera
Keyword(s):  
Hypervalent Iodine ◽  
Catalytic Method ◽  
Quaternary Centers ◽  
Mild Conditions ◽  
Reaction Proceeds ◽  
Mechanistic Investigations ◽  
Derivatives Of

An electrophilic enantioselective catalytic method for the a-pentafluoroethylation of alkyl 1-indanone-2-carboxylates is described. Under the use of La(OTf)<sub>3</sub> in combination with (<i>S,R</i>)-indanyl-<i>pybox</i> ligand good results in terms of yield and enantioselectivities were achieved (up to 89% <i>ee</i>). The reaction proceeds under mild conditions leading to the formation of enantioenriched quaternary centers. This methodology uses an hypervalent iodine(III)-CF<sub>2</sub>CF<sub>3</sub> reagent and mechanistic investigations are consistent with the involvement of a radical pathway.

Unterscheidung von Stickstoff- und Phosphor-Inversion, Rotation um die N-P-Bindung und Ligandenaustausch am Phosphor

1968 ◽  
Vol 23 (6) ◽  
pp. 759-766 ◽  
Author(s):  
D. Imbery ◽  
H. Friebolin
Keyword(s):  
Low Temperatures ◽  
Room Temperature ◽  
Nitrogen Inversion ◽  
Kinetic Processes ◽  
Derivatives Of

A large number of aminophosphines were prepared to study the kinetic processes. It could be shown that at room temperature there is rapid nitrogen-inversion but slow phosphorous-inversion. At higher temperatures ( + 80 °C), a rapid chlorine-exchange takes place with inversion of configuration at phosphorous. At low temperatures ( — 80 °C), rotation around the N-P-bond was slow. A dependence of the barrier of rotation on the size of the substituents could be recognized. It is possible that pπ-dπ-bonding is partially responsible for the relatively high barrier of rotation compared with derivatives of ethane and hydrazine.

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