Density effects of heavy-ion stopping power in high temperature matter

Abstract

The stopping power and range for Xe ions in high temperature matter (partially ionized plasmas) have been calculated using the dielectric response function method. Calculations have been made for a target matter Al (Z = 13) over a wide range of temperatures and densities considering a finite temperature model. The stopping powers obtained have smaller values in comparison with those of a zero temperature model. The stopping power strongly depends on the density and temperature of the target material, and the projectile ion energy.     

Synthesis and biological evaluation of novel phane-structured diazacrowns containing γ-piperidone and pyridine rings

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FACILE SYNTHESIS OF POLYSUBSTITUTED CYCLOPENTENYLAMINES OR γ-HYDROXYAMIDES BY SAMARIUM DIIODIDE

ABSTRACT

Promoted by SmI₂, γ-Hydroxyamides or polysubstituted cyclopentenylamines were synthesized from 1,1-diaryl-2,2-dicyanoethylenes or diaryl ketones and cinnamoyl amides under mild conditions in good yields.     

FT-IR Study of the Adsorption of Propane and Propene on V2O5/γ-Al2O3 Catalyst

It has been observed on the oxidized V₂ O₅/γ-Al₂ O₃ that C₃H₆ form alkoxides which were converted to acetone during the desorption of adsorbate phase at 373 K. C₃ H₈ may form π-complexes on the reduced form of the same catalyst. However, the intensities of the bands in the adadsorption of C₃ H₈ were very weak as compared with the case of C₃ H₆ adsorption. Therefore, it was not reasonable to assign these bands clearly as any of the surface type species.     

EtOAc-dispersed magnetic nanoparticles (DMNPs) of γ-Fe2O3 in the single-pot domino preparation of 5-oxo-2-thioxo-3-thiophenecarboxylate derivatives

EtOAc-dispersed magnetic nanoparticles (DMNPs) of γ-Fe₂O₃ represent a straightforward and green catalyst for the rapid three-component synthesis of 5-oxo-2-thioxo-3-thiophenecarboxylate derivatives as rhodanine skeletons via a single-pot domino process. The rhodanines were prepared over magnetic nanoparticles of γ-Fe₂O₃ without any salt or additives. Dispersed nano-γ-Fe₂O₃ have many advantages, such as stability in air, reusability, reactions with high efficiency, simple separation with magnetic external field from mixture reactions, chemical stability, and also low toxicity.     

Novel Approach for the Synthesis of N-Substituted-4-(2-methyl-4-oxo-4H-quinazolin-3-yl)-butyramides

A simple and convenient method for the synthesis of N-substituted-4-(2-methyl-4-oxo-4H-quinazolin-3-yl)-butyramides has been reported. Several aromatic and aliphatic amide derivatives of 4-(2-methyl-4-oxo-4H-quinazolin-3-yl)-butyric acid were prepared in 60–81% yields by refluxing it with different phosphazo compounds in toluene for approximately 1 h.     

Reactivity of Various α-Halo Ketones in One-Pot Synthesis of γ-Iminolactones

The highly reactive 1:1 intermediate generated in the reaction of tert-butyl isocyanide and dialkyl acetylenedicarboxylate is trapped by α-halo ketones to produce halogenated iminolactones as the sole product in good yields.     

Combination of Novozym 435–Catalyzed Hydrolysis and Mitsunobu Reaction for Production of (R)-γ-Lactones

Chiral γ-lactones of both enantiomers were synthesized with more than 90% optical purities. The key step was Novozym 435–catalyzed hydrolysis of racemic N-benzyl-4-acetoxyalkylamides. Additionally, because (R)-γ-lactones are predominant in apricot, mango, peach, passion fruit, and strawberry, synthesis was attempted using only one enantiomer selectively. The (R)-enantimer was synthesized with more than 80% total yield and more than 90% optical purity by a combination of Novozym 435–catalyzed hydrolysis and the Mitsunobu reaction.     

THE STEREOSELECTIVE SYNTHESIS OF N-ARYL-TRANS,TRANS-α-CARBOXYL-β-METHOXYCARBONYL-γ-ARYL-γ-BUTYROLACTAMS

Cis-1-methoxycarbonyl-2-aryl-6,6-dimethyl-5,7-diox-spiro-[2,5]-4,8-octadiones (1) in dimethyl ethylene glycol at room temperature react with anilines (2) to give N-aryl-trans,trans-α-carboxyl-β-methoxycarbonyl-γ-aryl-γ-butyrolactams (3) in good to excellent yields and high stereoselectivity.     

Stereoselective Synthesis and Characterization of (Z)-(−)-4-(1′-Alkoxyl-1′-alkyloxycarbonyl-methylidene)-5(R)-[(1R)-menthyloxy]-γ-butyrolactones

Abstract

A series of enantiomerically pure (Z)-(?)-4-(1′-alkyloxy-1′-alkyloxycarbonyl-methylidene)-5(R)-[(1R)-menthyloxy]-γ-butyrolactones were synthesized and characterized in good to excellent yields via O-alkylation of (4R,5R)-(?)-4-ethoxyoxalyl-5-[(1R)-menthyloxy]-γ-butyrolactone with alkyl halides in the presence of K₂CO₃ in acetone at room temperature.