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1.
The asymmetric transfer hydrogenation of a series of 2,2-dimethyl-6-(2-oxoalkyl)-1,3-dioxin-4-ones and 2,2-dimethyl-6-(2-oxoaryl)-1,3-dioxin-4-ones was achieved in high enantiomeric excess using a Ru(II) catalyst. The aryl substrates were most compatible with the methodology and this process facilitated a total synthesis of enantiomerically pure (+)-yashabushitriol. 相似文献
2.
Yu. S. Andreichikov D. D. Nekrasov M. A. Rudenko O. V. Vinokurova 《Chemistry of Heterocyclic Compounds》1989,25(9):1059-1061
Aroylketenes have been generated by thermolysis of 6-aryl-2,2-dimethyl-1,3-dioxin-4-ones. They take part in a 1,4-cycloaddition reaction at the CN bond of N-aryl or N,N-dialkyl-N-cyanoamines and of N'-phenyl-N-cyanoguanidine to form the corresponding 2-N-aryl-amino, 2-N,N-dialkylamino, and 2-N-phenylguanidino-6-aryl-1,3-oxazin-4-ones. p-Aminobenzonitrile and cyanoacetamide are acylated by aroylketenes to form the p-cyanophenylamide of p-toluylacetic acid and the cyano-acetamide of benzoylacetic acid.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1265–1268, September, 1989. 相似文献
3.
D. D. Nekrasov 《Chemistry of Heterocyclic Compounds》2001,37(8):925-938
Methods for the production of 6-aryl-2,2-dimethyl-1,3-dioxin-4-ones and their thermolysis in the presence of nucleophiles and dienophiles are discussed 相似文献
4.
Yu. S. Andreichikov O. V. Vinokurova V. L. Gein 《Chemistry of Heterocyclic Compounds》1989,25(2):126-128
Aroyl ketenes formed in the thermolysis of 6-aryl-2,2-dimethyl-1,3-dioxin-4-ones undergo a [4+2]-cycloaddition reaction with acetylacetone and methyl acylpyruvates to give 2-methyl- and 2-methoxycarbonyl-3-acyl-6-arylpyran-4-ones, respectively.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 161–163, February, 1989. 相似文献
5.
V. L. Gein S. G. Pitirimova Yu. S. Andreichikov M. F. Gordeev V. S. Bogdanov V. A. Dorokhov 《Russian Chemical Bulletin》1992,41(5):968-968
N. D. Zelenskii Institute of Organic Chemistry, Russian Academy of Sciences, 117913 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 5, pp. 1225–1226, May, 1992. 相似文献
6.
Dmitri V. Sevenard Andrey V. Didenko Denis Lorenz Michael Vorobiev Johannes Stelten Thomas Dülcks Vyacheslav Ya. Sosnovskikh 《Tetrahedron》2017,73(11):1495-1502
A simple and reliable method for the preparation of 2,2-dimethyl-5-(trifluoroacetyl)-1,3-dioxane-4,6-dione and 2,2-dimethyl-6-(trifluoromethyl)-4H-1,3-dioxin-4-one on a multigram scale was developed. These (trifluoroacetyl)ketene precursors were used in the hetero-Diels-Alder reaction with dialkylcyanamides and 1-ethoxyprop-1-yne, as well as in some reactions with nucleophiles. 相似文献
7.
We have used thermolysis of 6-aryl-2,2-dimethyl-1,3-dioxin-4-ones in the presence of N-cyanoaniline, pyridinium cyano(ethoxycarbonyl)methylide,
and 4-hydroxybenzonitrile to obtain the corresponding 6-aryl-2-phenylamino-1,3-oxazin-4-ones, pyridinium ethoxycarbonyl(4-oxo-6-aryl-4H-1,3-oxazin-2-yl)methylides,
and p-cyanophenyl esters of 3-aryl-3-oxopropanoic acids. We present the results of a preliminary investigation of the biological
activity of these compounds.
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Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 764–768, May, 2006. 相似文献
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V. A. Mamedov V. L. Mamedova G. Z. Khikmatova D. B. Krivolapov I. A. Litvinov 《Russian Chemical Bulletin》2016,65(5):1260-1267
A Darzens condensation of α-chloroacetamide with aromatic aldehydes furnished a series of 3-aryl-2,3-epoxypropionamides, which were further converted to 5-[bromo(aryl)methyl]-2,2-dimethyl-1,3-oxazolidin-2-ones. 相似文献
10.
Alkyl carbamates and S-alkyl thiocarbamates react with substituted malonyl dichlorides in boiling benzene to give the corresponding 2,5-substituted 4-hydroxy-6H-1,3-oxazin-6-ones. The reaction of S-methyl thiocarbamate with unsubstituted malonyl dichloride in boiling diethyl ether or benzene leads to formation of S-methyl (3-methylsulfanylaminocarbonyl-3-oxopropionyl)thiocarbamate and is not accompanied by cyclization, whereas in boiling toluene 4-hydroxy-2-methylsulfanyl-6H-1,3-oxazin-6-one is obtained.__________Translated from Zhurnal Obshchei Khimii, Vol. 75, No. 3, 2005, pp. 468–472.Original Russian Text Copyright © 2005 by Lalaev, Yakovlev, Zakhs. 相似文献
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(R)-5-Bromo-6-(bromomethyl)-2-(tert-butyl)-2H,4H-1,3-dioxin-4-one ( 2 ) derived from (R)-3-hydroxybutanoic acid is used for substitutions and chain elongations at the side-chain C-atom in the 6-position of the heterocycle (→ 3–6 , 10–13 ). Subsequent simultaneous reductive debromination and double-bond hydrogenation (Pd/C,H2)occurs with essentially complete diastereoselectivity (>98% ds), with H transfer from the face opposite to the t-Bu group (→ 15–20 , Table 1). Hydrolytic cleavages of the dioxanones then lead to enantiomerically pure β-hydroxy-acid derivatives (overall self-reproduction of the stereogenic center of 3-hydroxybutanoic acid or alkylation in the 4-position of this acid with preservation of configuration). 相似文献
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16.
The condensation of fluoroacetones with oxalyl fluoride in the presence of potassium fluoride has been shown to yield 2,2-di(fluoroalkyl)-5,5-difluoro-1,3-dioxolan-4-ones. 相似文献
17.
Reactions of 2,2-dimethyl-6-trifluoromethyl-2,3-dihydro-4-pyrone with ethylenediamine, hydrazine, or hydroxylamine yield 5-methyl-7-trifluoromethyl-2,3-dihydro-1H-1,4-diazepine, 3(5)-(2-hydroxy-2-methylpropyl)-5(3)-trifluoromethylpyrazole, and 5-hydroxy-3-(2-hydroxy-2-methylpropyl)-5-triflouromethyl-Δ2, respectively. The same compounds were obtained from 2-amino-1,1,1-trifluoro-6-hydroxy-6-methylhept-2(Z)-en-4-one and 2-hydroxy-6, 6-dimethyl-2-trifluoromethyltetrahydro-4-pyrone. 相似文献
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19.
S. G. Krivokolysko A. N. Chernega V. P. Litvinov 《Chemistry of Heterocyclic Compounds》2002,38(10):1269-1275
N-Methylmorpholinium 5-[2-cyanoethyl-1-(4-hydroxy-3-methoxyphenyl)-2-thiocarbamoyl]-2,2-dimethyl-6-oxo-1,3-dioxa-4-cyclohexen-4-olate was obtained from the reaction of 4-hydroxy-3-methoxybenzaldehyde with cyanothioacetamide and Meldrum's acid in the presence of N-methylmorpholine. The molecular and crystal structure of the title compound have been established and its alkylation has been studied. 相似文献