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排序方式: 共有198条查询结果,搜索用时 15 毫秒
1.
Raskulova T. V. Volkova L. I. Danilevich Yu. S. Shainyan B. A. Khaliullin A. K. 《Russian Journal of Organic Chemistry》2002,38(5):754-755
Russian Journal of Organic Chemistry - 相似文献
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E. N. Suslova A. I. Albanov B. A. Shainyan 《Russian Journal of General Chemistry》2005,75(8):1234-1242
Synthetic approaches to 4,4-dimethyl-1,4-thiasilinane and its S-functional derivatives, 4,4-dimethyl-1,4-thiasilinane S-oxide, 4,4-dimethyl-1,4-thiasilinane S,S-dioxide, 4,4-dimethyl- 1-(phenylsulfonylimino)-1,4-thiasilinane, and 1,4,4-trimethyl-1,4-thiasilinan-1-ylium iodide, were studied. The S-functional derivatives of 4,4-dimethyl-4-thiasilinane, unlike 3,3-dimethyl-3-thiasilinane, are hydrolytically stable. 相似文献
4.
The catalytic reduction of acetophenone, methyl α-acetamidocinnamate, and dimethyl itaconate with alcohol-modified sodium borohydride was studied in the presence of complexes CoCl2·L2 (L2 are chiral C
2-symmetric diamines: (4S,5S)-2,2-dimethyl-4,5-bis(aminomethyl)-1,3-dioxolane, (4S, 5S)-2,2-dimethyl-4,5-bis(methylaminomethyl)-1,3-dioxolane, (4S, 5S)-2,2-dimethyl-4,5-bis(dimethylaminomethyl)-1,3-dioxolane, and (4S, 5S)-2,2-dimethyl-4,5-bis(diphenylaminomethyl)-1,3-dioxolane). The maximum enantiomeric excess of (S)-1-phenylethanol was 24%, that of dimethyl α-methylsuccinate was 38%.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 342–347, February, 2005. 相似文献
5.
Nindakova L. O. Shainyan B. A. Albanov A. I. Shmidt F. K. 《Russian Journal of Organic Chemistry》2003,39(7):926-932
The catalytic activity and stereoselectivity in the hydrogenation of itaconic and -(acetylamino)cinnamic acids were studied in the presence of the complex [Rh(COD)(L1)2]+ TfO- (where COD is cyclooctadiene and L1 is (1S,2S,5R)-(+)-neomenthyldiphenylphosphine] which was generated in situ. The optical yield of the hydrogenation of itaconic acid increases both on addition of chiral (4S,5S)-(+)-2,2-dimethyl-4,5-bis(dimethylaminomethyl)-1,3-dioxolane (L2) as an auxiliary ligand to the complex [Rh(COD)(L1)2]+ TfO- and on addition of achiral and chiral tertiary phosphines to the complex [Rh(L2)2]+ TfO-. The result of joint action of two ligands can be regarded as "matched effect." Transformations of the complexes in a hydrogen atmosphere were examined by 1H and 3
1P NMR spectroscopy. It was found that at least three complexes: diamine complex [Rh(L2)2]+ TfO-, solvate complex [Rh(L1)2(solv)2]+ TfO-, and diamine-bis-phosphine complex [Rh(L1)2L2]+ TfO- may be catalytic precursors. 相似文献
6.
N-Sulfinyltrifluoromethanesulfonamide CF3SO2N=S=O reacts with salicylaldehyde, 2-furaldehyde, 2-thiophenecarbaldehyde, 3-methyl-1-phenyl-1H-pyrazole-4-carbaldehyde, and 2-phenyl-2H-1,2,3-triazole-4-carbaldehyde to afford the corresponding N-aryl(hetaryl)methylidenetrifluoromethanesulfonamides in high yields. Reactions of the latter with aniline give no adducts at the C=N bond but transamination products. The reaction of trifluoromethanesulfonamide with phenyl isocyanate led to formation of N,N′-diphenylurea instead of expected N-phenyl-N′-(trifluoromethylsulfonyl)urea.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 7, 2005, pp. 1006–1010.Original Russian Text Copyright © 2005 by Shainyan, Tolstikova. 相似文献
7.
2-Phenyl-4-trifluoromethylsulfonylmethyl-2H-1,2,3-triazole was synthesized from 4-bromo-methyl-2-phenyl-2H-1,2,3-triazole and sodium trifluoromethanesulfinate CF3SO2Na. 1(2)-Ethyl-4-nitro-1(2)H-1,2,3-triazoles and 4-nitro-2-phenyl-2H-1,2,3-triazole were reduced to the corresponding amines. Intermediate 1,2-bis(1-ethyl-1H-1,2,3-triazol-4-yl)diazene 1-oxide exists as a mixture of syn and anti isomers, the former being stabilized via formation of a strong intramolecular hydrogen bond. The reduction of 2-ethyl-4-nitro-2H-1,2,3-triazole in the presence of HCl afforded the target 4-amino-2-ethyl-2H-1,2,3-triazole and also 4-amino-5-chloro-2-ethyl-2H-1,2,3-triazole. Treatment of alkyl-substituted 4-amino-1,2,3-triazoles with trifluoromethanesulfonyl chloride and pentafluoroethanesulfonyl chloride gave N-triazolyl-substituted trifluoromethane- and pentafluoroethanesulfonamides and -imides. 相似文献
8.
A one-pot synthesis of linear and cyclic β-alkoxyselenides is developed through the iodine-mediated three-component reaction of elemental selenium with alkenes (dienes) and alcohols. Selenylation of 1,5-hexadiene gives 2,5-di(methoxymethyl)tetrahydroselenophene and 2-methoxy-6-(methoxymethyl)tetrahydro-2H-selenopyran via the 5-exo-trig and 6-endo-trig cyclization. 1,7-Octadiene affords only linear 1:2 adduct with two terminal double bonds. 1,5-Cyclooctadiene results in one diastereomer of 2,6-dialkoxy-9-selenabicyclo [3.3.1]nonanes via 6-exo-trig cyclization. With 1,3-diethenyl-1,1,3,3-tetramethyldisiloxane, the first ring-substituted representative of a very rare class of heterocycles, 1,4,2,6-oxaselenadisilinanes, was obtained at a high yield. 相似文献
9.
Anton S. Ganin Mikhail Yu. Moskalik Ivan A. Garagan Vera V. Astakhova Bagrat A. Shainyan 《Molecules (Basel, Switzerland)》2022,27(20)
Allyl halides with triflamide under oxidative conditions form halogen-substituted amidines. Allyl cyanide reacts with triflamide in acetonitrile or THF solutions in the presence of NBS to give the products of bromotriflamidation with a solvent interception, whereas in CH2Cl2 two regioisomers of the bromotriflamidation product without a solvent interception were obtained. The formed products undergo base-induced dehydrobromination to give linear isomers with the new C=C bond conjugated either with the nitrile group or the amidine moiety or alkoxy group. Under the same conditions, the reaction of allyl alcohol with triflamide gives rise to amidine, which was prepared earlier by the reaction of diallyl formal with triflamide. Unlike their iodo-substituted analogs, bromo-substituted amidines successfully transform into imidazolidines under the action of potassium carbonate. 相似文献
10.