A rapid method for the preparation of 87Y/87mSr radionuclide generator from a rubidium chloride target irradiated with 35 MeV α-particles is described. A simple two-step
procedure is used to obtain a carrier-free 87mSr isotope with a high enough radiochemical yield and high purity in the final aqueous fraction. 相似文献
The behavior of (pyrrol-1-yl)furazans in electrophilic substitution reactions (halogenation, nitration, and acylation) was
studied. The presence of the furazan ring substantially did not affect the regioselectivity of the reactions but it prevented
replacement of all the hydrogen atoms in the pyrrole ring by electrophiles.
Dedicated to Academician V. A. Tartakovsky on the occasion of his 75th birthday.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1516–1520, August, 2007. 相似文献
A “one-pot” method for the synthesis of 3-alkyl-4-aminofurazans from ethyl β-alkyl-β-oxopropionates was developed. The multistep
process involves hydrolysis of the ester, nitrosation at the activated methylene group, and treatment of the resulting intermediate
with an alkaline solution of hydroxylamine in the presence of urea.
Dedicated to Corresponding Member of the Russian Academy of Sciences E. P. Serebryakov on the occasion of his 70th birthday.
__________
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 1007–1012, April, 2005. 相似文献
4-Methoxybenzyl chloride reacts with elemental (red or white) phosphorus under the conditions of phase-transfer catalysis (concentrated aqueous KOH, dioxane, benzyltriethylammonium chloride, 85-90°C, argon) to give as major product tris(4-methoxybenzyl)phosphine oxide in up to 45% yield. With white phosphorus at lower (70°C) temperature this reaction yields mainly bis(4-methoxybenzyl)phosphine oxide. Phosphine reacts with 4-methoxybenzyl chloride in superbasic KOH-DMSO suspension, and under definite conditions bis(4-methoxybenzyl)phosphine oxide is predominantly formed. 相似文献
Reactions of isopropyl 2-(1-aryl-4,5-dioxo-2-phenyl-4,5-dihydro-1H-pyrrol-3-yl)-2-oxoacetates with aromatic amines involve a pyrroledione-pyrroledione recyclization to form isopropyl 1-aryl-2-hydroxy-4,5-dioxo-3-[phenyl(arylamino)methylene]pyrrolidine-2-carboxylates.
The crystal and molecular structure of (Z)-isopropyl 2-hydroxy-4,5-dioxo-1-phenyl-3-[phenyl(phenylamino)methylene]pyrrolidine-2-carboxylate was proved by XRD analysis. 相似文献
The synthesis of new indoline spiropyran by the cyclocondensation in methanol revealed that the free aldehyde group of the target spiropyran is easily converted into the dimethyl acetal moiety without the addition of an acid catalyst, giving 8′-dimethoxymethyl-1,3,3-trimethylspiro[indoline-2,2′-2H-chromene]-5,6′-dicarboxylic acid as a single reaction product. The structure of this compound was confirmed by NMR spectroscopy and mass spectrometry. The molecular structure was also established by single-crystal X-ray diffraction. The Hirshfeld surfaces were generated and analyzed and intermolecular interactions in the crystal were investigated using the CrystalExplorer software package. The reverse hydrolysis reaction of dimethyl acetal to the aldehyde group proceeds under mild conditions in dimethyl sulfoxide, as shown by NMR spectroscopy.
Russian Journal of General Chemistry - Depending on the ring size in the Reformatsky reagent and the nature of substituents in arylmethylidene fragment, the reactions of Reformatsky reagents... 相似文献
A magnetic transition accompanied by a sharp decrease in magnetization has been detected in an (NdSmDy)(FeCo)B alloy at temperature T = 110 K. It is found that the sample undergoes a spin-reorientation transition accompanied with a change in the type of magnetic anisotropy. The “easy axis”-type anisotropy corresponds to high temperatures T > 110 K. A magnetic structure of the type of “the cone of easy-magnetization axes” forms at low temperatures T < 110 K. 相似文献
Physics of the Solid State - The heats of wetting have been measured experimentally for some of the solvents used for the preparation of electrolytes of supercapacitors. For the first time, the... 相似文献