• Bulletin of the Korean Chemical Society
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• v.13 no.2
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• pp.184-187
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• 1992

Regeneration methods of oximes, hydrazones, and N,N-dimethylhydrazones to the related carbonyl compounds were effected using various dicarbonyl compounds which are activated with electron withdrawing substituents such as trifluoromethylated $\beta-diketones$, $\beta-acylpyruvates$, and $\alpha-diketones$ via an equilibrium exchange reaction. The chemical transformations of the dicarbonyl compounds in the exchange reaction were investigated by various spectroscopic methods.

• Bulletin of the Korean Chemical Society
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• v.32 no.5
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• pp.1697-1702
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• 2011

A facile, green, efficient and environment-friendly protocol for the synthesis of 14-aryl- or alkyl-14Hdibenzo[a,j]xanthene, 1,8-dioxooctahydroxanthene and 12-aryl-8,9,10,12-tetrahydrobenzo[a]xanthene-11-one have been developed by one-pot condensation of various aldehydes with (i) ${\beta}$-naphthol (ii) cyclic 1,3-dicarbonyl compounds and (iii) ${\beta}$-naphthol and cyclic 1,3-dicarbonyl compounds, in the presence of 1,3,5-trichloro-2,4,6-triazinetrion (trichloroisocyanuric acid, TCCA) as catalyst under solvent-free conditions. The present approach offers the advantages of clean reaction, simple methodology, short reaction time, easy purification, and economic availability of the catalyst.

• Bulletin of the Korean Chemical Society
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• v.29 no.6
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• pp.1195-1198
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• 2008

Kinetic studies of the additions of benzylamines to a noncyclic dicarbonyl group activated olefin, methyl $\alpha$-acetyl-$\beta$ -phenylacrylates (MAP), in acetonitrile at 30.0 ${^{\circ}C}$ are reported. The rates are lower than those for the cyclic dicarbonyl group activated olefins. The addition occurs in a single step with concurrent formation of the $C_\alpha$ -N and $C_\beta$ -H bonds through a four-center hydrogen bonded transition state. The kinetic isotope effects ($k_H/k_D$ > 1.0) measured with deuterated benzylamines ($XC_6H_4CH_2ND_2$) increase with a stronger electron acceptor substituent ($\delta\sigma$ X > 0) which is the same trend as those found for other dicarbonyl group activated series (1-4). The sign and magnitude of the cross-interaction constant, ρXY, is comparable to those for the normal bond formation processes in the $S_N2$ and addition reactions. The relatively low ${\Delta}H^\neq$ and large negative ${\Delta}S^\neq$ values are also consistent with the mechanism proposed.

• Journal of Photoscience
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• v.2 no.2
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• pp.73-76
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• 1995

The photohydration of 1-(m-nitrophenyl)-5, 5-dimethyl-1, 3-hexadiyne (m-NDHD) affords allenyl ketone compound (1) via triplet excited state which is converted into $\beta$-dicarbonyl compound (2) through thermal hydration. The allenyl ketone is formed by the synchronous addition of water with protonation at C$_1$ indicating that m-NDHD has the reverse polarization and greater electron withdrawing effect in the triplet excited state in comparison with p-NDHD.

• Bulletin of the Korean Chemical Society
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• v.23 no.7
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• pp.998-1002
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• 2002

An efficient synthesis of 2H-pyrans is achieved by indium (III) chloride-catalyzed reactions of 1,3-dicarbonyl compounds with a variety of $\alpha\beta-unsaturated$, aldehydes in moderate yields. This method has been applied to the synthesis of pyranocoumar ins, pyranophenalenones, and pyranoquinolinone alkaloids.

• Rapid Communication in Photoscience
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• v.1 no.1
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• pp.17-18
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• 2012

Photoaddition reactions between 1,2-dicarbonyl compounds and silyl enol ethers in acetonitrile and benzene were explored. Irradiation of acetonitrile or benzene solutions containing 1,2-diketone, acenaphthalquinone, phenanthrene-quinone and silyl enol ethers is observed to promote the production of 1,4-dioxenes, oxetanes, and ${\beta}$-hydroxyketone by the [4+2]-cycloadditon, Paterno-Buchi processes, and SET promoted Claisen-type condensation. Among these competitive pathways leading to the generation of each types of products, SET promoted 1,4-dioxene and ${\beta}$-hydroxyketone formation are more favored regardless of solvent polarity.

• Bulletin of the Korean Chemical Society
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• v.32 no.5
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• pp.1543-1546
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• 2011

N-Bromosaccharin/$Mg(ClO_4)_2$ is an effective and regioselective system for ${\alpha}$-monobromination of 1,3-dicarbonyl compounds. A wide variety of ${\beta}$-keto esters and 1,3-diketones in reaction with this system afforded a regioselectively ${\alpha}$-monobrominated products. The bromination reaction can be conducted at 0-5 $^{\circ}C$ either in solution or under solvent-free conditions.

• Bulletin of the Korean Chemical Society
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• v.31 no.11
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• pp.3238-3240
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• 2010

A new and efficient method for the preparation of substituted 3,4-dihydropyrimidin-2(1H)-ones via Biginelli synthesis using catalytic amounts of 1,3-dichloro-5,5-dimethylhydantoin is presented. Short reaction times, easy work-up, high yields of products and stability, easy-handling, non-toxicity and cheapness of the catalyst are noteworthy advantages of the present work.

• Bulletin of the Korean Chemical Society
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• v.29 no.9
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• pp.1752-1754
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• 2008

A simple and efficient synthesis of 3,4-dihydropyrimidinones or thiones is described, using silica-supported perchloric acid ($HClO_4-SiO_2$) as a heterogeneous catalyst from an aldehyde, $\beta$-dicarbonyl compound, and urea or thiourea under solvent-free conditions. Compared to the classical Biginelli reactions, this method consistently has the advantage of high yields, short reaction time, easy separation, and tolerance towards various functional groups.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.1
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• pp.45-51
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• 1986

Equimolar aqueous solutions of D-glucose and glycine were heated at $50^{\circ}C\;and\;95^{\circ}C$ at pH 6.7. The headspace volatiles and the ether extracts from the reaction mixture were analyzed by gas chromatography and gas chromatography-mass spectrometry using a fused silica capillary column. The major components formed were identified as diacetyl, three furfurals, two pyrroles, one furanone, two pyranones and two amides. In order to elucidate the formation mechanisms of the amides formed front amino-carbonyl reaction, two model systems were adopted. N-butylacetamide were formed as major components from diacetyl-butylamine ana glyoxal-butylamine systems, respectively. The results obtained suggest that such ${\alpha}-dicarbonyls$ as 3-deoxy-D-erythro-2,3-hexodiulose and diacetyl generated in the amino-carbonyl reaction react with amino compounds, amides then being formed by cleavage of the C-C bond in the ${\alpha}-dicarbonyls$.