• Title/Summary/Keyword: Solvent-free 조건

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Regioselective Synthesis of Z-Aldoximes Catalyzed By H3PMo12O40 under Solvent-Free Conditions (Solvent-free 조건하에서 H3PMo12O40 촉매에 의한 Z-Aldoximes의)

  • Eshghi, Hossein;Alizadeh, Mohammad Hasan;Davamdar, Ehsan
    • Journal of the Korean Chemical Society
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    • v.52 no.1
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    • pp.52-56
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    • 2008
  • facile and efficient method for the preparation of Z-aldoximes is improved by means of H3PMo12O40 catalyst in solvent-free media. The major advantages of this method are: operational simplicity, low catalyst loading, selectivity, mild reaction conditions, short reaction times and excellent yields. The recovered catalyst could be used in new attempts without any purification.

Microwave-induced one-pot Synthesis of Coumarins Using Potassium Dihydrogen Phosphate as a Catalyst Under Solvent-free Condition (무 용매 조건에서 potassium dihydrogen phosphate를 촉매로 사용하는 쿠마린의 마이크로파-유도 단일 용기 내 합성)

  • Niralwad, Kirti S.;Shingate, Bapurao B.;Shingare, Murlidhar S.
    • Journal of the Korean Chemical Society
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    • v.55 no.3
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    • pp.486-489
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    • 2011
  • Potassium dihydrogen phosphate was found to be an efficient catalyst for the Pechmann condensation of phenols with ethyl acetoacetate, leading to the formation of coumarins under microwave-irradiation and solvent-free condition. This procedure offers several advantages, including the low loading of catalysts, high yields, clean reactions, short reaction time for the synthesis of coumarins.

Dry Media Reaction Procedure for Synthesis of α,β-Unsaturated Acids, α-Cyanoacrylonitriles and α-Cyanoacrylates via Knoevenagel Condensation Using NaHSO4·SiO2 Catalyst (NaHSO4·SiO2 촉매를 이용한 Knoevenagel 축합을 거친α,β의 불포화산, α-Cyanoacrylonitriles와 α-Cyanoacrylates의 합성을 위한 무수조건하의 반응 절차)

  • Gopalakrishnan, M.;Sureshkumar, P.;Kanagarajan, V.;Thanusu, J.;Thirunavukkarasu, S.
    • Journal of the Korean Chemical Society
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    • v.51 no.4
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    • pp.346-351
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    • 2007
  • Efficient stereoselective synthesis of α,β-Unsaturated acids, α-Cyanoacrylonitriles and α-Cyanoacrylates has been carried out in the presence of NaHSO4·SiO2 under solvent?free conditions with an E-geometry.

NaHSO4/SiO2: An Efficient Catalyst for the Synthesis of β-Enaminones and 2-Methylquinolin-4(1H)-Ones under Solvent-Free Condition (NaHSO4/SiO2: Solvent-Free 반응 조건에서 β-Enaminone들과 2-Methylquinolin-4(1H)-One들의 합성을 위한 효율적인 촉매)

  • Sapkal, Suryakant B.;Shelke, Kiran F.;Shingate, Bapurao B.;Shingare, Murlidhar S.
    • Journal of the Korean Chemical Society
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    • v.54 no.6
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    • pp.723-726
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    • 2010
  • An efficient and simplified protocol for $NaHSO_4/SiO_2$ catalyzed solvent-free synthesis of $\beta$-enaminone and 2-methylquinolin-4(1H)-one derivatives under microwave irradiation is described. A series of functionalized derivatives have been synthesized in shorter reaction times with moderate to good yields. The use of milder catalyst in non-conventional method offers significant advantages over conventional methods, such as higher selectivities, simplicity, solvent-free reaction and non-environmental polluting conditions.

Surface Free Energy Change of Polypropylene Film treated by Atmospheric Pressure Plasma (대기압 플라즈마로 처리된 폴리프로필렌 필름의 표면 자유에너지 변화)

  • Kwon, Oh June;Tang, Shen;Lu, Na;Choi, Ho Suk
    • Journal of Adhesion and Interface
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    • v.4 no.4
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    • pp.1-6
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    • 2003
  • After atmospheric pressure plasma treatment of polypropylene(PP) film surface, we measured the contact angle of the surface by using polar solvent (water) and non-polar solvent (diiodomethane). We also calculated the surface free energy of PP film by using the measured values of contact angles. And then we analyzed contact angle and surface free energy with changing the condition of atmospheric pressure plasma treatment. Upon each condition of atmospheric plasma treatment, contact angle and surface free energy showed an optimum value or leveled off.

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Iron (III) Phosphate as a Green and Reusable Catalyst Promoted Chemo Selective Acetylation of Alcohols and Phenols with Acetic Anhydride Under Solvent Free Conditions at Room Temperature (친환경 촉매 Iron (III) phosphate: 실온/무용매 반응조건에서 알코올과 페놀의 선택적인 아실화 반응)

  • Behbahani, F.K.;Farahani, M.;Oskooie, H.A.
    • Journal of the Korean Chemical Society
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    • v.55 no.4
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    • pp.633-637
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    • 2011
  • Iron (III) phosphate was employed as an efficient catalyst for the chemo selective acetylation of alcohols and phenols under solvent free condition at room temperature and with high yields. Iron (III) phosphate is also a potential green catalyst due to solid intrinsically, reusable and with high catalytic activity.

Silica Sulfuric Acid/Wet $SIO_2$as a Novel System for the Deprotection of Acetals by Using Microwave Irradiation under Solvent Free Conditions (무용매 조건하에서 황산/젖은 $SIO_2$와 마이크로웨이브를 이용한 아세탈의 새로운 탈보호기 방)

  • BiBi Fathemeh, Mirjalili; Mohammad Ali, Zolfigol;Abdolhamid, Bamoniri
    • Journal of the Korean Chemical Society
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    • v.45 no.6
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    • pp.546-548
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    • 2001
  • Neat chlorosulfonic acid reacts with silica gel to give silica sulfuric acid in which sulfuric acid is immobilized on the surface of silica gel via covalent bond. A combination of silica sulfuric acid and wet SiO$_2$ was used as an effective deacetalizating agent for the conversion of acetals to their corresponding carbonyl derivatives by using microwave irradiation under solvent free conditions.

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The Study on the Efficacy of Herbal Plant Extracts by the Part and Solvent Extraction (약용식물의 부위별 및 추출용매에 따른 효능 연구)

  • Kim, Hyung-Dong;Kim, Sang-Jin
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.33 no.2
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    • pp.127-135
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    • 2007
  • This study was to evaluate the efficiency of different solvent systems to extract active ingredients from different parts of medicinal plants used as oriental medicinal herb in the cosmetic industry. We tested efficacies related to the antioxidative effects and UV absorption of herbal extracts as complex of active ingredients, not each single ingredient. When extracting medicinal plant which is used effective medicine, we should consider the collecting conditions like collecting time, place, part and extracting conditions like solvent, temperature, time, and etc. Among them, extraction solvent and collecting part are very important factors for the efficacy. As increased interest in medicinal plants, more intensive studies on collecting conditions and extracting processes were needed for the developments in the herbal ingredient industry. We evaluated the efficiency of different solvent systems to extract active ingredients from different parts of plants (Terminalia chebula, Syzygium aromaticum, Paeonia lactiflora, Morus alba, Scutellaria baicalensis) widely used as medicine and food. As results, we found that proper condition can make better data and decrease the required quantity.

Characteristics of Coals Extracted Using Solvent at Mild and High Temperature Conditions (온순조건과 고온조건에서 용매 추출한 석탄의 특성 비교)

  • Park, Keun Yong;Choi, Ho Kyung;Kim, Sang Do;Yoo, Ji Ho;Chun, Dong Hyuk;Rhim, Young Joon;Lim, Jeong Han;Lee, Si Hyun;Na, Byung Ki
    • Applied Chemistry for Engineering
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    • v.23 no.6
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    • pp.529-533
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    • 2012
  • In this study, we compare various physicochemical properties of solvent extracted coals obtained at both mild and high temperature conditions. In order to characterize the extraction behavior, experiments were performed using a sub-bituminous coal (Kideco) and a polar solvent (N-methyl-2-pyrrolidinone, NMP), where the extraction temperature and the effect of solvent recycling were evaluated. As the extraction temperature increased up to $350^{\circ}C$, an extraction yield and a calorific value of the extracted coal increased, while an ash content of the extracted coal decreased. FT-IR results revealed that the surface of the coal extracted at $350^{\circ}C$ was found to contain more amide, aromatic ester, and aliphatic ether groups than that at the lower temperatures. The result of MALDI-TOF/MS analysis confirmed that the smaller molecules with 300~500 m/z were extracted at a mild condition, while the bigger molecules in the range of 500~1500 m/z were extracted at the high temperature.

Synthesis of Diacylglycerol-Enriched Functional Lipid Containing DHA by Lipase-Catalyzed in Solvent-Free System (비 용매계에서 DHA가 함유된 Diacylglycerol의 효소적 반응에 의한 합성연구)

  • Kim, Nam-Sook;Lee, Ki-Teak
    • Korean Journal of Food Science and Technology
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    • v.37 no.4
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    • pp.584-589
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    • 2005
  • Structured triacylglycerol (SL-TAG) was synthesized by enzymatic interesterification with algae oil and soybean oil in solvent-free system. Structured di- and monoacylglycerol (SL-DAG/MAG) were produced by glycerolysis with SL-TAG and glycerol catalyzed by lipase. Reactions were performed by sn-1.3 specific Lipozyme RM IM lipase from Rhizomucor miehei (interesterification, 11%; glycerolysis 5% by weight of total substrates) in solvent-free system using stirred-batch type reactor. SL-DAG/MAG contained TAG (42,3 area%), 1,3-DAG (19.2 area%), 1,2-DAG (22.2 area%), MAG (16.0 area%), and free fatty acid (0.2 area%). Iodine and saponification values of SL-DAG/MAG were 208.8 and 179.6, respectively. SL-DAG/MAG appeared yellowish in color.