Rapid and Efficient Coupling Reaction of Azo Dyes in a Continuous-Flow Microreactor

2012 ◽  
Vol 560-561 ◽  
pp. 516-520
Author(s):  
Wu Bin Yu ◽  
Ming Ming Zheng ◽  
Jian Rong Gao
Keyword(s):  
Reaction Time ◽  
Azo Dyes ◽  
Continuous Flow ◽  
Room Temperature ◽  
High Efficiency ◽  
Coupling Reaction ◽  
Reaction Conditions ◽  
Short Reaction Time ◽  
Flow Microreactor ◽  
Efficient Coupling

A convenient, rapid efficient method for the synthesis of azo dyes has been developed by coupling in a continuous-flow microreactor at room temperature. The advantage of this protocol is its continuousness, high efficiency and selectivity, short reaction time, and milder reaction conditions.

Efficient Copper-Catalyzed Synthesis of Substituted Pyrazoles at Room Temperature

Synlett ◽  
2018 ◽  
Vol 29 (20) ◽  
pp. 2689-2692 ◽  
Author(s):  
Haifeng Wang ◽  
Xiangli Sun ◽  
Shuangling Zhang ◽  
Guanglu Liu ◽  
Chunjie Wang ◽  
...  
Keyword(s):  
Reaction Time ◽  
Catalytic System ◽  
Efficient Method ◽  
Room Temperature ◽  
Copper Catalyst ◽  
Condensation Reaction ◽  
Reaction Conditions ◽  
Short Reaction Time ◽  
Acid Catalyzed ◽  
Substituted Pyrazoles

An efficient method for the synthesis of pyrazoles through a copper-catalyzed condensation reaction has been developed. The new catalytic system not only maintained a broad substrate scope but was also active under acid-free reaction conditions, overcoming the conventional requirement for an acid-catalyzed system. Furthermore, the copper catalyst enabled this reaction to be performed at room temperature and in a short reaction time.

Convenient and Efficient Synthesis of Thiol Esters using Zinc Oxide as a Heterogeneous and Eco-Friendly Catalyst

2008 ◽  
Vol 61 (12) ◽  
pp. 1006 ◽  
Author(s):  
Babasaheb Pandurang Bandgar ◽  
Parmeshwar Eknath More ◽  
Vinod Tribhuvannathji Kamble ◽  
Sanjay Suresh Sawant
Keyword(s):  
Zinc Oxide ◽  
Reaction Time ◽  
Room Temperature ◽  
Efficient Synthesis ◽  
Catalytic Method ◽  
Reaction Conditions ◽  
Acyl Chlorides ◽  
Short Reaction Time ◽  
Thiol Esters ◽  
Solvent Free Conditions

A catalytic method was developed to synthesize thiol esters from the reaction of acyl chlorides and thiols using zinc oxide as a catalyst under solvent-free conditions at room temperature. Mild reaction conditions, short reaction time, excellent yields of products and recyclability of the catalyst are noteworthy features of this methodology.

Solvent-free, Silica Catalyzed Intriguing Conversion of 3-Hydrazonobutan-2-one Oxime into Biacetyl Bis-hydrazone Schiff Bases

2020 ◽  
Vol 17 ◽  
Author(s):  
Ranjana Aggarwal ◽  
Mona Hooda ◽  
Prince Kumar ◽  
Garima Sumran
Keyword(s):  
Reaction Time ◽  
Schiff Bases ◽  
Good Yield ◽  
Room Temperature ◽  
Environmentally Benign ◽  
Reaction Conditions ◽  
Short Reaction Time ◽  
Free Silica ◽  
Elemental Analyses ◽  
Unexpected Product

: An expeditious and operationally simple reaction between 3-hydrazonobutan-2-one oxime and different substituted benzaldehydes in presence of silica afforded an unexpected product, biacetyl bis-hydrazone Schiff bases in good yield on grinding in a mortar at room temperature, instead of expected product 3-(aryl)methylenehydrazonobutan-2-one oxime. Mild reaction conditions involving recyclable mineral support silica, environmentally benign and good yield in short reaction time are remarkable advantages of this protocol. Products were characterized by IR, NMR (1H and 13C) and elemental analyses.

Copper-Catalyzed Highly Efficient Esterification of Aldehydes with N-Hydroxyphthalimide via Cross-Dehydrogenative Coupling in Water at Room Temperature

Synlett ◽  
2017 ◽  
Vol 28 (11) ◽  
pp. 1321-1326 ◽  
Author(s):  
Can Jin ◽  
Weike Su ◽  
Zhicheng Guo ◽  
Xinpeng Jiang ◽  
Jiadi Zhou ◽  
...  
Keyword(s):  
Reaction Time ◽  
Efficient Method ◽  
Room Temperature ◽  
Coupling Reaction ◽  
Short Reaction Time ◽  
Mild Conditions ◽  
Highly Efficient ◽  
Dehydrogenative Coupling ◽  
First Time

A copper-catalyzed cross-dehydrogenative coupling reaction between N-hydroxyphthalimide and aldehydes using PhI(OAc)2 as an oxidant is described. It is reported for the first time to synthesize NHPI esters in water, providing the corresponding NHPI esters in moderate to good yields. This facile and efficient method is eco-friendly and possesses the advantages of mild conditions, short reaction time, and broad substrate scope.

Tyrosine-Selective Bioconjugation with Iminoxyl Radicals

2020 ◽  
Author(s):  
Katsuya Maruyama ◽  
Takashi Ishiyama ◽  
Yohei Seki ◽  
Kounosuke Oisaki ◽  
Motomu Kanai
Keyword(s):  
Reaction Time ◽  
Steric Hindrance ◽  
Room Temperature ◽  
Water Soluble ◽  
Light Irradiation ◽  
Sodium Ascorbate ◽  
Iminoxyl Radical ◽  
Short Reaction Time ◽  
Modified Peptides ◽  
The Stability

A novel Tyr-selective protein bioconjugation using the water-soluble persistent iminoxyl radical is described. The conjugation proceeded with high Tyr-selectivity and short reaction time under biocompatible conditions (room temperature in buffered media under air). The stability of the conjugates was tunable depending on the steric hindrance of iminoxyl. The presence of sodium ascorbate and/or light irradiation promoted traceless deconjugation, restoring the native Tyr structure. The method is applied to the synthesis of a protein-dye conjugate and further derivatization to azobenzene-modified peptides.

Transformation of 1-Butene over Synthetic Zeolites

1992 ◽  
Vol 57 (4) ◽  
pp. 869-881 ◽  
Author(s):  
Italo Ferino ◽  
Roberto Monaci ◽  
Vincenzo Solinas ◽  
Lucio Forni ◽  
Antonio Rivoldini ◽  
...  
Keyword(s):  
Atmospheric Pressure ◽  
Continuous Flow ◽  
Liquid Mixture ◽  
Isomerization Reaction ◽  
Reaction Conditions ◽  
Title Reaction ◽  
Y Zeolites ◽  
Temperature Range ◽  
Flow Microreactor ◽  
Synthetic Zeolites

The behaviour of several zeolites as catalysts for the title reaction has been investigated by means of a continuous flow microreactor. Runs performed at atmospheric pressure indicated that at 423 K the completely protonic forms of the zeolites catalyze just the isomerization reaction. In the case of Y zeolites, oligomerization occurs only over the partially decationated samples, in the temperature range between 373 and 423 K and W/F between 0.2 and 22 gcath/g1-but, to an extent which depends on the reaction conditions. Most of the catalysts were tested also under pressure (4.05 MPa) at 423 K. The protonic forms of Y and ZSM-5 zeolites seem promising catalysts in terms of both conversion and selectivity to oligomers. The 1-olefins account for 30% of the entire olefinic mixture. The octenes, which account for 70% of the liquid mixture, are mostly formed of dimethylhexenes. Trimers are also formed during the reaction and, in the very particular case of H[B]ZSM-5, tetramers are produced.

scholarly journals The Eschenmoser coupling reaction under continuous-flow conditions

2011 ◽  
Vol 7 ◽  
pp. 1164-1172 ◽  
Author(s):  
Sukhdeep Singh ◽  
J Michael Köhler ◽  
Andreas Schober ◽  
G Alexander Groß
Keyword(s):  
Continuous Flow ◽  
Elevated Temperatures ◽  
Reaction Times ◽  
Coupling Reaction ◽  
Flow Chemistry ◽  
Flow Conditions ◽  
Reaction Conditions ◽  
Bond Forming ◽  
Carbon Carbon Bond ◽  
Reaction Proceeds

The Eschenmoser coupling is a useful carbon–carbon bond forming reaction which has been used in various different synthesis strategies. The reaction proceeds smoothly if S-alkylated ternary thioamides or thiolactames are used. In the case of S-alkylated secondary thioamides or thiolactames, the Eschenmoser coupling needs prolonged reaction times and elevated temperatures to deliver valuable yields. We have used a flow chemistry system to promote the Eschenmoser coupling under enhanced reaction conditions in order to convert the demanding precursors such as S-alkylated secondary thioamides and thiolactames in an efficient way. Under pressurized reaction conditions at about 220 °C, the desired Eschenmoser coupling products were obtained within 70 s residence time. The reaction kinetics was investigated and 15 examples of different building block combinations are given.

Hypervalent Iodine(III)-Catalyzed Epoxidation of β-Cyanostyrenes

Synthesis ◽  
2019 ◽  
Vol 51 (23) ◽  
pp. 4473-4486 ◽  
Author(s):  
Saeesh R. Mangaonkar ◽  
Fateh V. Singh
Keyword(s):  
Reaction Time ◽  
Room Temperature ◽  
Hypervalent Iodine ◽  
Short Reaction Time ◽  
Convenient Approach

A convenient approach for the synthesis of β-cyanoepoxides is illustrated by iodine(III)-catalyzed epoxidation of electron-deficient β-cyanostyrenes, wherein the active catalytic iodine(III) species was generated in situ. The epoxidation of β-cyanostyrenes was performed using 10 mol% PhI as precatalyst in the presence of 2.0 equivalents Oxone as an oxidant and 2.4 equivalents of TFA as an additive at room temperature under ultrasonic radiations. The β-cyanoepoxides were isolated in good to excellent yields in a short reaction time.

Desulfurization from Gasoline by Polymer Resin at Room Temperature and Atmospheric Pressure

2011 ◽  
Vol 396-398 ◽  
pp. 1283-1286
Author(s):  
Jian Peng Zhu ◽  
Chun Hu Li ◽  
Jia Ling Chen ◽  
Ying Wei Luo
Keyword(s):  
Reaction Time ◽  
Sulfur Content ◽  
Atmospheric Pressure ◽  
Room Temperature ◽  
Oxidative Desulfurization ◽  
Sulfur Compounds ◽  
Molar Ratio ◽  
Reaction Conditions ◽  
Polymer Resin ◽  
Mild Conditions

Abstract. Investigation of polymer resin as catalyst in the oxidative desulfurization (ODS) process has revealed that the method can be applied to make a relative high removal of sulfur compounds. The reaction conditions, including temperature, amount of oxidant and reaction time were studied. The best result occurs under mild conditions with respect to room temperature and atmospheric pressure, to remove 75.54% of the totle sulfur content in the presence of H2O2 with an O/S molar ratio of 17. Possible mechanism is also disscussed.

Synthesis of Epihalohydrins by Dehydrohalogenation of Glycerol Dihalohydrins - Utilization of a Basic Ion-Exchange Resin

1992 ◽  
Vol 45 (8) ◽  
pp. 1327
Author(s):  
M Dargelos ◽  
ME Borredon ◽  
A Gaset
Keyword(s):  
Reaction Time ◽  
Ion Exchange ◽  
Room Temperature ◽  
Exchange Resin ◽  
Ion Exchange Resin ◽  
Organic Medium ◽  
Short Reaction Time ◽  
Hydrolysis Of

Dehydrohalogenation of a mixture of glycerol 1,3- and 2,3-dihalohydrins by a strong basic ion-exchange resin (IRA 440 and A 26) at room temperature in an organic medium quantitatively leads to the corresponding epihalohydrin (1a; X = Cl), and (1b; X = Br) in a very short reaction time. Hydrolysis of the epihalohydrin does not occur under these conditions.

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