• Bulletin of the Korean Chemical Society
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• 제29권12호
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• pp.2445-2448
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• 2008

• Bulletin of the Korean Chemical Society
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• 제32권5호
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• pp.1703-1708
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• 2011

ZSM-5-$SO_3H$ efficiently catalyzed the one-pot three-component Mannich reaction of aldehydes, anilines, and ketones. ${\beta}$-Aminocarbonyl compounds were obtained in reasonable yields and excellent stereoselectivities when the reaction was carried out at room temperature under solvent-free conditions. Simple experimental conditions and product isolation procedure makes this protocol potential for the development of clean and environment-friendly strategy for the synthesis of ${\beta}$-amino-ketones. The catalyst was recovered and reused for subsequent runs.

• 대한화학회지
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• 제55권3호
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• pp.486-489
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• 2011

Potassium dihydrogen phosphate는 마이크로파 조사조건에서 용매 없이 페놀과 아세토아세트산 에틸의 Pechmann 축합반응에 의하여 쿠마린을 합성하는 효과적인 촉매로 밝혀졌다. 이 방법은 쿠마린 합성에 있어서 소량의 촉매를 필요로 하며 수율이 높고, 반응이 깨끗할 뿐만 아니라 반응 시간이 짧은 장점들을 가지고 있다.

• Bulletin of the Korean Chemical Society
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• 제32권1호
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• pp.175-178
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• 2011

A facile, convenient, efficient and high yielding synthesis of a combinatorial library of coumarins has been developed by the condensation of readily available $\beta$-oxodithioesters and S,S-acetal with 2-hydroxy-1-naphthaldehyde in the presence of catalytic amount of $CuCl_2$ under solvent free conditions.

• 대한화학회지
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• 제55권6호
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• pp.936-939
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• 2011

Thiamine hydrochloride (VB1) has been used as an acid catalyst in organic synthesis. One pot three component Biginelli condensation of dimedone, urea/thiourea and substituted aromatic aldehydes catalyzed by 10 mol % of thiamine hydrochloride (VB1) in solvent free condition under microwave irradiation in good to excellent yields has been investigated. Utilization of microwave irradiation, simple reaction conditions, short reaction time, ease of product isolation, and purification makes this manipulation very interesting from an economic and environmental perspective.

• 대한화학회지
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• 제51권4호
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• pp.346-351
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• 2007

NaHSO4·SiO2를 사용하는 solvent-free 조건하에서 E-geometry를 가진 α,β의 불포화산, α-Cyanoacrylonitriles 와 α-Cyanoacrylates의 효율적인 입체선택적 반응을 수행하였다.

• Bulletin of the Korean Chemical Society
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• 제32권5호
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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.

• Food Science and Biotechnology
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• 제14권3호
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• pp.368-370
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• 2005

Citronellyl valerate was synthesized by a lipase from a Rhizopus sp strain isolated and the lipase produced, at UNICAMP, Brazil. Direct esterification was performed in a solvent-free medium to produce the flavor ester. Response surface methodology was used to optimize the process with respect to the substrate molar ratio and lipase concentration. The results show that the synthesis of citronellyl valerate can be carried out in a solvent-free medium, the maximum ester conversion rate achieved being 91.5% after 48 hours of reaction time.

• Bulletin of the Korean Chemical Society
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• 제33권10호
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• pp.3196-3202
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• 2012

Post-synthesis is used to synthesize organic hybrid inorganic mesoporous sieves. In this method, the activity and structure of the base sieve are crucial to obtain the definable hybrid materials. The chemical and physical properties of the base can be largely changed either by the final step of its synthesizing processes, by template removal which is accomplished with the oxidative thermal decomposition (burning) method or by solvent extraction method. In this paper we compared two methods for the post-synthesis of organic hybrid MCM-48. When the template was extracted with HCl/alcohol mixture, the final product showed larger pore size, larger pore volume and better crystallinity compared to the case of the thermal decomposition. The reactivity of the surface silanol group of template free MCM-48 was also checked with an alkylsilylation reagent $CH_2=CHSi(OC_2H_5)_3$. Raman and $^{29}Si$ NMR spectra of MCM-48 in the test reaction indicated that more of the organic group was grafted to the surface of the sample after the template was removed with the solvent extraction method. Direct synthesis of vinyl-MCM-48 was also investigated and its characteristics were compared with the case of post-synthesis. From the results, it was suggested that the structure and chemical reactivity can be maintained in the solvent extraction method and that organic grafting after the solvent extraction can be a good candidate to synthesize a definable hybrid porous material.

• 대한화학회지
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• 제51권6호
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• pp.591-594
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• 2007