• Bulletin of the Korean Chemical Society
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• v.35 no.6
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• pp.1654-1658
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• 2014

High value-added aromatic aldehydes (e.g. vanillin and syringaldehyde) were produced from heavy fraction of bio-oil (HFBO) via catalytic oxidation. The concept is based on the use of metalloporphyin as catalyst and hydrogen peroxide ($H_2O_2$) as oxidant under alkaline condition. The biomimetic catalyst cobalt(II)-sulfonated tetraphenylporphyrin ($Co(TPPS_4)$) was prepared and characterized. It exhibited relative high activity in the catalytic oxidation of HFBO. 4.57 wt % vanillin and 1.58 wt % syringaldehyde were obtained from catalytic oxidation of HFBO, compared to 2.6 wt % vanillin and 0.86 wt % syringaldehyde without $Co(TPPS_4)$. Moreover, a possible mechanism of HFBO oxidation using $Co(TPPS_4)/H_2O_2$ was proposed by the research of model compounds. The results showed that this is a promising and environmentally friendly method for production of aromatic aldehydes from HFBO under $Co(TPPS_4)/H_2O_2$ system.

• Bulletin of the Korean Chemical Society
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• v.31 no.8
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• pp.2289-2292
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• 2010

Long chain dicationic ammonium salts were used successfully as phase transfer catalyst in the condensation reactions of aromatic aldehydes in water under ultrasonic irradiation for the first time. The quaternary salt having longer distance between the cation centers was more effective than the mono- and dicationic ones having short chain.

• Journal of the Korean Chemical Society
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• v.51 no.5
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• pp.418-422
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• 2007

A simple and high yielding one-pot method for synthesis of 2,4,5-triarylimidazoles from condensation of benzoin or benzil, ammonium acetate and aromatic aldehydes using sulphanilic acid catalyst is described. The lower priced catalyst, higher yields and shorter reaction time are the advantages of the presented method.

• Bulletin of the Korean Chemical Society
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• v.33 no.7
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• pp.2129-2130
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• 2012

• Bulletin of the Korean Chemical Society
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• v.23 no.12
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• pp.1697-1698
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• 2002

• Bulletin of the Korean Chemical Society
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• v.26 no.2
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• pp.265-267
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• 2005

An efficient method of addition of trimethylsilyl cyanide to aldehydes by employing a zirconium complex as the catalyst has been described. A variety of aromatic, aliphatic, cyclic and heterocyclic aldehydes has been converted into corresponding trimethylsilyl ethers in excellent yield within short reaction time.

• Archives of Pharmacal Research
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• v.25 no.3
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• pp.258-269
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• 2002

2-Thiouracil-5-sulfonylchloride 1 reacted with a series of aromatic and heterocyclic amines to give 2a-j. The same compound 1 was reacted with a series of sulphonamides giving different sulphonamides of type 3a-e. On the other hand compound 1 was allowed to react with p-aminoacetophenone givining compound 4 which in turn was allowed to react with derivatives of alkyl thiosemicarbazides to give thiosemicarbazones of type 5a-e, also compound 4 was monobrominated to give compound 6 which in turn was reacted thiosemicarbazones of some aldehydes to give the corresponding thiazole derivatives 7a-f. In the same time compound 4 was reacted with a series of aromatic and heterocyclic aldehydes givining chalcones 8a-g (Claisen-Schemidt reaction). Also compound 4 was allowed to react with a series of aromatic and heterocyclic aldehydes, ethyl cyano acetate and/or malononitrile, and ammonium acetate giving pyridine derivatives 9a-d and 10a-e respectively. The biological effects of some of the new synthesized compounds was also investigated.

• The Korean Journal of Food And Nutrition
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• v.30 no.1
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• pp.120-128
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• 2017

This study aimed to provide volatile flavor compounds of three onion products through thermal process and alcohol fermentation, to meet the quality standard of onion products. The identified components of onion extracts (OE) included 49 (18 sulfur-containing compounds, 5 alcohols, 8 acids, 3 ketones, 4 esters, 4 aromatic compounds, 2 aldehydes, 1 pyrazines and 4 miscellaneous compounds), and 55 (17 sulfur-containing compounds, 15 alcohols, 5 acids, 11 ketones, 3 aromatic compounds, 2 aldehydes and 1 pyrazine) in autoclave-sterilized onion extracts (SOE); and 69 (10 sulfur-containing compounds, 27 alcohols, 11 acids, 11 ketones, 6 esters, 1 aromatic compound and 3 pyrazines) in onion wine (OW), respectively. Among the major flavor classes, sulfur-containing compounds (36.8%), acids (31.3%) and aldehydes (13.6%) in OE were changed to alcohols (46.5%) and ketones (27.3%) in SOE whereas, alcohols (56.3%) and acids (26.6%) in OW. Moreover, 1,3-butanediol, 2,3-butanediol, and 3-hydroxy-2-butanone were highly detected in SOE whereas, acetic acid, 3-methylbutanol, 2-phenylethanol and 1,2,3-propanetriol in OW.

• Bulletin of the Korean Chemical Society
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• v.27 no.8
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• pp.1203-1205
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• 2006

During the synthesis of 4-fluorobenzaldehyde via the SNAr reaction of 4-nitrobenzaldehyde with TBAF, it was found that an equivalent amount of TBAF could oxidize benzaldehyde to benzoic acid. The reaction of 4-nitrobenzaldehyde with tetrabutylammonium fluoride (TBAF) gave 4-nitrobenzoic acid in high yield. Depending on the reaction conditions, other aromatic aldehydes produced acids with fewer amounts of alcohols. However, this type of oxidation has limited practical applications. Nevertheless, the mechanism is quite different from the Cannizzaro reaction because the amounts of the acid salt and alcohol formed were different.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.2
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• pp.299-304
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• 1999

To compare the composition of volatile flavor components of two different types of rice, the volatile flavor concentrates isolated from brown rices Hyangnambyeo(aromatic cultivar) and Dongjinbyeo (normal cultivar) were analyzed by gas chromatography and gas chromatography mass spectrometry. A total of components, including 16 hydrocarbons, 16 aldehydes and ketones, 15 alcohols, 4 acids, and 10 miscellaneous components were identified positively or tentat ively. Among them, n pentanol was the most abundant component in both samples and Hyangnambyeo contained more aldehydes and alcohols than Dongjinbyeo. 2 Acetyl 1 pyrroline which is chiefly responsible for the character istic odor of aromatic type rice was high in Hyangnambyeo compare to Dongjinbyeo, but these were detected as minor component.