• Title/Summary/Keyword: Mild synthesis conditions

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Immobilization of L-Lysine on Zeolite 4A as an Organic-Inorganic Composite Basic Catalyst for Synthesis of α,β-Unsaturated Carbonyl Compounds under Mild Conditions

  • Zamani, Farzad;Rezapour, Mehdi;Kianpour, Sahar
    • Bulletin of the Korean Chemical Society
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    • v.34 no.8
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    • pp.2367-2374
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    • 2013
  • Lysine (Lys) immobilized on zeolite 4A was prepared by a simple adsorption method. The physical and chemical properties of Lys/zeolite 4A were investigated by X-ray diffraction (XRD), FT-IR, Brunauer-Emmett-Teller (BET), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and UV-vis. The obtained organic-inorganic composite was effectively employed as a heterogeneous basic catalyst for synthesis of ${\alpha},{\beta}$-unsaturated carbonyl compounds. No by-product formation, high yields, short reaction times, mild reaction conditions, operational simplicity with reusability of the catalyst are the salient features of the present catalyst.

Process Development for Large Scale Synthesis of TRH (TRH의 대량합성 제조법 개발)

  • Kim, Dong-Hyeon;Thapa, Pritam;Karki, Radha;Jahng, Yurng-Dong;Lee, Eung-Seok
    • YAKHAK HOEJI
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    • v.51 no.6
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    • pp.490-494
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    • 2007
  • TRH (thyrotropin-releasing hormone) was chemically synthesized utilizing solution phase peptide chemistry for the process development of large scaled synthesis. All the synthetic steps performed in relatively mild conditions, higher yields, easier preparations, minimum racemizations, and separation and purification by recrystallizations.

Silica Sulfuric Acid/HNO3 as a Novel Heterogeneous System for the Nitrolysis of DADN to HMX under Mild Conditions

  • Bayat, Yadollah;Mostafavi, Mohammad Mahdi Ahari
    • Bulletin of the Korean Chemical Society
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    • v.33 no.11
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    • pp.3551-3553
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    • 2012
  • 1,5-Diacetyl-3,7-dinitro-l,3,5,7-tetraazacyclooctane (DADN) is a key intermediate in the preparation of octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX), one of the most powerful high-melting explosives. The present investigation focuses on nitrolysis of DADN to HMX by developing a new nitrolysis process involving the use of nitric acid catalyzed by Silica Sulfuric Acid (SSA). In order to optimize the process parameters for synthesis of HMX to obtain higher yield and purity, a study was carried out with variation of some parametric conditions like time, mole ratio of SSA and nitric. This method gave us green and mild conditions for nitration reaction.

Mild and Efficient Synthesis of Sodium Dodecanoyl-4-oxybenzenesulfonate using Water and Polar Aprotic Solvent Mixed System and Its Application as a Bleach Activator (물과 극성 비양자성 용매 혼합 계를 이용한 4-도데카노일옥시벤젠술폰산 나트륨의 효율적인 합성 및 표백활성화제로의 응용)

  • Kwak, Sang-Woon;Cha, Kyung-on;Jeong, Kook-In;Kim, Young-Ho
    • Applied Chemistry for Engineering
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    • v.32 no.5
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    • pp.532-540
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    • 2021
  • Sodium dodecanoyl-4-oxybenzenesulfonate (DOBS) salt is a substance that exhibits effective bleaching and antimicrobial abilities at low temperatures. A mild and efficient synthesis method of DOBS starting from dodecanoyl chloride and sodium 4-hydroxybenzene sulfonate was investigated under alkaline conditions using a water (W)-polar aprotic solvent system. First, the reaction was carried out using only water as a solvent system with the variables of temperature and time. The yield was found to be as low as about 5% in most cases under the reaction conditions of more than 30 ℃ and 1 h. In order to develop an efficient solvent system, the effect on the yield of DOBS was evaluated in various solvent systems which were prepared by changing the type of polar aprotic solvents while mixing them with the water. A solvent system in which acetone (AC) and water were mixed showed the best yield and about 82 % under mild reaction conditions (30 ℃, 1 h and atmospheric pressure) was obtained. The prepared DOBS showed good bleaching and antimicrobial activities indicating that it could be used an excellent bleach activator.

Synthesis and luminescent properties of $Eu^{3+}$-doped $YVO_4$ by using a mild hydrothermal process

  • Moon, Young-Min;Choi, Sung-Ho;Lim, Sang-Ho;Jung, Ha-Kyun
    • 한국정보디스플레이학회:학술대회논문집
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    • 2008.10a
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    • pp.784-787
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    • 2008
  • Nanoscale $YVO_4:Eu^{3+}$ phosphor has been synthesized by a mild hydrothermal reaction at various experimental conditions. The particle and luminescent properties of nanophosphors were characterized with X-ray diffraction, electron microscopy and photoluminescence. It has been found that pH value play a key factor both controlling particle size and luminous efficiency.

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An Efficient Synthesis of 2,4,5-Triaryl-1H-Imidazole Derivatives Catalyzed by Boric Acid in Aqueous Media Under Ultrasound-Irradiation

  • Shelke, Kiran F.;Sapkal, Suryakant;Sonal, Swapnil;Madje, Balaji R.;Shingate, Bapurao B.;Shingare, Murlidhar S.
    • Bulletin of the Korean Chemical Society
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    • v.30 no.5
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    • pp.1057-1060
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    • 2009
  • Boric acid ($BO_3H_3$) is an inexpensive, efficient and mild catalyst for the synthesis of 2,4,5-triaryl-1H-imidazoles in excellent yields from the one-pot three-component condensation of benzil/benzoin, an aldehydes and ammonium acetate in aqueous media under ultrasound at room temperature. The remarkable advantages offered by this method are green catalyst, mild reaction conditions, simple procedures, much faster reactions and excellent yield of products.

A Simple and Efficient One-Pot Three-Component Synthesis of Propargylamines Using Bismuth (III) Chloride

  • Teimouri, Abbas;Chermahini, Alireza Najafi;Narimani, M.
    • Bulletin of the Korean Chemical Society
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    • v.33 no.5
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    • pp.1556-1560
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    • 2012
  • A simple highly versatile and efficient method has been developed for the three-component coupling of aldehydes, amines and alkynes to prepare propargylamines, in the presence of a catalytic amount of $BiCl_3$. The advantages of methods are high yield, mild reaction conditions, no environmental pollution and easy work up procedure.

Efficient Synthesis of β-Acetamido Ketones by Silver(I) Triflate-Catalyzed Multicomponent Reactions

  • Pandit, Rameshwar Prasad;Lee, Yong Rok
    • Bulletin of the Korean Chemical Society
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    • v.33 no.11
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    • pp.3559-3564
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    • 2012
  • An efficient one-pot synthesis of ${\beta}$-acetamido ketones was accomplished by AgOTf-catalyzed multicomponent reactions of substituted acetophenones with aromatic aldehydes and acid chloride in acetonitrile in high yields. The methods offer several significant advantages of easy handling, mild reaction conditions, and use of effective and non-toxic catalyst.