• Bulletin of the Korean Chemical Society
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• 제8권4호
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• pp.301-304
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• 1987

A systematic study of the partial reduction of nitriles to the corresponding aldehydes with thexylbromoborane-methyl sulfide $(ThxBHBr{\cdot}SMe_2)$ under practical conditions has been carried out. The yields of aldehydes are good in the aliphatic series. However, the yields of aromatic series vary with substituents and ring itself.

• Bulletin of the Korean Chemical Society
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• 제8권5호
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• pp.435-436
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• 1987

• Bulletin of the Korean Chemical Society
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• 제13권4호
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• pp.451-453
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• 1992

• Bulletin of the Korean Chemical Society
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• 제14권2호
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• pp.302-303
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• 1993

• 한국작물학회지
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• 제44권3호
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• pp.181-185
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• 1999

To compare the composition of volatile flavor components of three different cultivars of rice, Hyangnambyeo (aromatic cultivar), Heugjinjubyeo (pigmented cultivar) and Dongjinbyeo (normal cultivar), the volatile flavor components of brown rice were isolated by Likens-Nickerson simultaneous steam distillation and extraction apparatus. The flavor concentrates obtained were analyzed by gas chromatography and gas chromatography-mass spectrometry. A total of 65 components, including 14 aliphatic aldehydes and ketones, 7 aliphatic alcohols, 8 aromatic alcohols, 13 hydrocarbons, 9 esters, 7 aliphatic acids, and 7 miscellaneous components were identified. The aliphatic aldehydes, which are known as contributors to the overall flavor of cooked rice, were present in larger amounts in Hyangnambyeo than in Heugjinjubyeo and Dongjinbyeo, while the difference in quantity of these components between Heugjinjubyeo and Dongjinbyeo was not remarkable. Hyangnambyeo and Heugjinjubeyo contained 562 ng and 259 ng of 2-acetyl-1-pyrroline per gram of brown rice based on dry weight, respectively, which is a key compound contributing to the popcorn-like aroma in aromatic rice. Dongjinbeyo contained about 6 ng.

• Bulletin of the Korean Chemical Society
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• 제13권6호
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• pp.670-676
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• 1992

A systematic study of the partial reduction of carboxylic acids and their derivatives to the corresponding aldehydes with lithium tris(dialkylamino)aluminum hydrides under practical conditions has been carried out. The diethylaminosubstituted derivative of lithium aluminum hydride, lithium tris(diethylamino)aluminum hydride (LTDEA), shows quite general applicability in the conversion of carboxylic acids, carboxylic esters, and primary carboxamides to the corresponding aldehydes. Lithium tripiperidinoaluminum hydride (LTPDA) also appears to be a reagent of choice for such partial transformation of primary carboxamides. In additioin, both LTDEA and LTPDA reduce tertiary carboxyamides to aldehydes in high yields. Finally, lithium tris(dihexylamino)aluminum hydride (LTDHA) is capable of achieving the chemoselective reduction of aromatic nitriles to aldehydes in the presence of aliphatic nitriles under practical conditions.

• Bulletin of the Korean Chemical Society
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• 제26권11호
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• pp.1677-1681
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• 2005

Aldol condensation of 2-acetylthiophene, 2-acetylpyrrole and 2-acetylpyridine with different aromatic aldehydes were carried out in water in heterogeneous phases in the presence of cetyltrimethylammonium bromide as cationic surfactant at room temperature. All the reactions occur in a short time with excellent yields of steroselective hetarylpropanones in water as environmental friendly solvent.

• Bulletin of the Korean Chemical Society
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• 제32권12호
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• pp.4286-4290
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• 2011

A novel catalytic synthesis of biscoumarins from 4-hydroxycoumarin and aromatic aldehydes has been developed. The reaction occurs in ethanol in the presence of tetrabutylammonium hexatungstate $[TBA]_2[W_6O_{19}]$ as catalyst to give the corresponding products in high yields. This new approach has short reaction times, clean reaction profiles, and simple experimental and workup procedures. Moreover, the catalyst can be easily recovered by filtration and used at least three times with only slight reduction in its catalytic activity.

• Bulletin of the Korean Chemical Society
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• 제27권1호
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• pp.106-110
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• 2006

Photocatalytic electron transfer reactions of aryl benzyl sulfides using 2,4,6 triphenylpyrilium tetrafluoroborate ($TP^+BF_4^-$) resulted in the oxidation of these sulfides to the corresponding sulfoxides and also in most cases in the C-S bond cleavage of them along with formation of aromatic aldehydes. In these reactions, the formation of sulfide radical cation has been proposed, which undergoes either oxidation to the corresponding sulfoxide or C-S bond cleavage to the formation of aromatic aldehydes. The further oxidation of sulfoxides to sulfones has not been observed. The influence of substrate structures on the reaction pathways as well as the role of $O_2$ in this respect is discussed.

• Bulletin of the Korean Chemical Society
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• 제20권5호
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• pp.528-530
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• 1999

The synthesis of a series of 6-aryl-2,4-dioxoperhydro-1,3,5-triazines by the condensation of biuret with aromatic aldehydes in trifloroacetic acid, is described.