78605-07-9Relevant academic research and scientific papers
Ir(bis-NHC)-Catalyzed Direct Conversion of Amines to Alcohols in Aqueous Glycerol
Cheong, Yeon-Joo,Lee, Seunghyeon,Hwang, Sang Joon,Yoon, Woojin,Yun, Hoseop,Jang, Hye-Young
supporting information, p. 1940 - 1943 (2019/02/25)
Sustainable catalytic conversion of amines to alcohols was realized in the presence of iridium catalysts and aqueous glycerol. Iridium catalysts involving bis-N-heterocyclic carbene (bis-NHC) show good reactivity and stability in the conversion of amines into alcohols in aqueous glycerol. The reaction was initiated with the dehydrogenation of amines and followed by hydrolysis and reduction. Iridium catalysts play dual roles in both the dehydrogenation and reduction steps. By employing glycerol as a solvent and hydrogen source, the final reduction was facilitated. The synthesis and characterization of various Ir(bis-NHC) complexes are described along with the catalytic reaction results of the amine into alcohol conversion.
Silica gel an efficient catalyst for one-pot synthesis of pyrazines from ethylenediamine and 1, 2-diketones and their analogs
Chakraborty, Rakesh Ranjan,Singha, Rabindranath,Ghosh, Pranab
, p. 373 - 378 (2018/09/29)
A straightforward one-pot synthesis of pyrazines from ethylenediamine and 1, 2-diketones/ α-hydroxy ketone/α-bromo ketone under solvent-free conditions at room temperature is described. This environmentally benign process has the edge on previous methods in respect of workup procedure, ease and cost of reaction, and use and generation of hazardous substances. The catalyst is recovered, characterized, and proved to be recyclable for successive four runs examined with appreciable conversions.
Clean and green approach for one-pot synthesis of pyrazines from Eth-ylenediamine and 1,2-diketone or its analogues under neat reaction condition
Ghosh, Pranab,Chakraborty, Rakesh Ranjan
, p. 566 - 570 (2017/09/29)
Background: Compounds having N-heterocyclic moieties are of huge importance in the field of agrochemical, pharmaceutical, biological, fragrances, etc. Due to a lot of applications associated with pyrazine moieties, their synthesis has always been important for organic chemists. Method: Surfeit synthetic methodologies are documented in literature. Most of the methodologies used expensive solvents, harmful metal catalyst and all suffer from rigorous work-up procedures. An efficient, environmentally benign methodology, needs to be developed. We mixed ethylenediamine (2mmol) with 1, 2-diketone(1mmol), later, α-hydroxy ketone and α-bromo ketone on magnetic stirrer at room temperature under neat reaction condition for 5 to 10 hrs. Results: After purification by column chromatography using silica gel(60-120 mesh) and pet-ether, et-hylacetate mixture as eluent, we achieved pyrazine derivatives from moderate to high yield. Conclusio n: Efficient and clean procedure for one-pot preparation of pyrazines from ethylenediamine and 1, 2-diketones or with α-hydroxy ketone or with α-bromo ketone has been carried out under neat reaction condition at room temperature. Environmentally benign process furnishing moderate to excellent yields of the product and simple work-up giving pure products are special features of this reaction.
Synthetic method of quinoxaline heterocyclic compound
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Paragraph 0020; 0021, (2016/10/09)
The invention provides a synthetic method of a quinoxaline heterocyclic compound. A quinoxaline heterocyclic derivative is prepared through one step by carrying out oxidation and cyclic condensation reaction on benzoin and ortho-diamine under the catalysis of a non-transition metal catalyst. According to the method, low-price and easily-available benzoin is used as a raw material, a water-soluble non-transition metal is used as a catalyst and convenient, economical and safe air is used as a direct oxidant to synthesize a target heterocyclic compound through one step at room temperature or a temperature slightly higher than the room temperature; the reaction condition is simple and mild; and inert gas protection is not needed as the synthesis is carried out in the air. The method is easy to operate, the only byproduct is water, the product is simple and easy to separate and purify, the yield is high, and the reaction condition requirement is relatively low, so that the method is wide in application range and has good research and industrial application prospects.
γ-Maghemite-silica nanocomposite: A green catalyst for diverse aromatic N-heterocycles
Ghosh, Pranab,Mandal, Amitava,Subba, Raju
, p. 146 - 152 (2013/09/02)
γ-Maghemite-silica nanocomposite has been applied as a green catalyst to synthesize variety of aromatic N-heterocycles under solvent free conditions. Characterization was done by modern analytical tools (UV, IR, AAS, DSC, EDXRF, powdered XRD, EPR, Mo?ssbauer and TEM). Mild reaction conditions and recyclability have made the present protocol both environmentally and economically viable.
Catalyst-free protocol for the synthesis of quinoxalines and pyrazines in PEG
Huang, Tie-Qiang,Qu, Wen-Yan,Ding, Jin-Chang,Liu, Miao-Chang,Wu, Hua-Yue,Chen, Jiu-Xi
, p. 293 - 297 (2013/06/05)
A facile and simple catalyst-free protocol has been developed for the condensation of 1,2-diketones with aromatic 1,2-diamines in polyethylene glycol (PEG), providing quinoxaline derivatives in good yields. The important features of the methodology are broad substrates scope, simple workup, catalyst free, environmentally benign, and no requirement for metal catalysts. It is noteworthy that the cyclization reaction of 1,2-diketones with aliphatic 1,2-diamines is also conducted smoothly to afford pyrazines in good yields under the standard conditions. In addition, PEG could be recovered easily and was reused without evident loss in activity
YbCl3-catalyzed one-pot synthesis of dihydropyrazines, piperazines, and pyrazines
Fan, Liyan,Chen, Wen,Qian, Changtao
, p. 231 - 234 (2013/02/23)
A simple and efficient synthetic approach to dihydropyrazines via YbCl 3-catalyzed reaction of α-hydroxyketones with diamines under mild conditions was developed. The corresponding 2,3-subsitituted piperazines and pyrazines were obtained through tandem conversion of dihydropyrazines with good yields.
Silica sulfuric acid (SSA)/polyethylene glycol (PEG) as a recyclable system for the synthesis of quinoxalines and pyrazines
Huang, Tieqiang,Jiang, Danna,Chen, Jiuxi,Gao, Wenxia,Ding, Jinchang,Wu, Huayue
experimental part, p. 3334 - 3343 (2011/09/19)
An efficient and facile method has been developed for the condensation of 1,2-diamines with-hydroxyketones in polyethylene glycol (PEG) to quinoxalines and pyrazines with good yields in the presence of silica sulfuric acid (SSA). The important features of the methodology are simple operations, environmentally friendliness, and no requirement for metal catalysts. Additionally, the catalyst system (SSA/PEG) could be recovered easily and reused.
Pyrazine derivatives useful as platelet aggregation inhibitors
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, (2008/06/13)
Novel pyrazine derivatives are disclosed. The compounds possess a potent platelet aggregation-inhibiting activity and are effective for preventing diseases caused by aggregation of the platelet, for example, myocardial infarction and cerebral thromobsis.
INTRODUCTION OF THE METHYL GROUP INTO THE PYRAZINE RING
Ohta, Akihiro,Inoue, Akira,Watanabe, Tokuhiro
, p. 2317 - 2321 (2007/10/02)
By the coupling reaction of mono- and dichloropyrazines with trimethylaluminum in the presence of a palladium catalyst, the corresponding mono- and dimethylpyrazines were prepared in excellent yields.
