scholarly journals DBU Catalyzed Phospho-Aldol-Brook Rearrangement for Rapid Preparation of α-Phosphates Amide in Solvent-Free Conditions

Catalysts ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1445
Author(s):  
Shunhong Chen ◽  
Shengxin Guo ◽  
Feng He ◽  
Yingxia Zhang ◽  
Zengxue Wu ◽  
...  

The 1,8-diazabicyclo [5.4.0] undec-7-ene DBU-catalyzed Phospho-Aldol-Brook Rearrangement reaction of α-ketoamide and dialkyl phosphites was developed under solvent-free at room temperature. The novel α-Phosphate Amide derivatives could be obtained with good yield (86–96%), which also exhibited good tolerance of various dialkyl phosphites and α-ketoamide, including isatins. In addition, the reaction was conducted in both gram-scale and mol-scale, and the title compounds could also be obtained in excellent yield (more than 91%) within 5 min.

2018 ◽  
Vol 21 (8) ◽  
pp. 602-608 ◽  
Author(s):  
Zainab Ehsani-Nasab ◽  
Ali Ezabadi

Aim and Objective: In the present work, 1, 1’-sulfinyldiethylammonium bis (hydrogen sulfate) as a novel room temperature dicationic ionic liquid was synthesized and used as a catalyst for xanthenediones synthesis. Material and Method: The dicationic ionic liquid has been synthesized using ethylamine and thionyl chloride as precursors. Then, by the reaction of [(EtNH2)2SO]Cl2 with H2SO4, [(EtNH2)2SO][HSO4]2 was prepared and after that, it was characterized by FT-IR, 1H NMR, 13C NMR as well as Hammett acidity function. This dicationic ionic liquid was used as a catalyst for the synthesis of xanthenediones via condensation of structurally diverse aldehydes and dimedone under solvent-free conditions. The progress of the reaction was monitored by thin layer chromatography (ethyl acetate/n-hexane = 3/7). Results: An efficient solvent-free method for the synthesis of xanthenediones has been developed in the presence of [(EtNH2)2SO][HSO4]2 as a powerful catalyst with high to excellent yields, and short reaction times. Additionally, recycling studies have demonstrated that the dicationic ionic liquid can be readily recovered and reused at least four times without significant loss of its catalytic activity. Conclusion: This new dicationic ionic liquid can act as a highly efficient catalyst for xanthenediones synthesis under solvent-free conditions.


2006 ◽  
Vol 36 (16) ◽  
pp. 2363-2369 ◽  
Author(s):  
Liangce Rong ◽  
Xiaoyue Li ◽  
Haiying Wang ◽  
Daqing Shi ◽  
Shujiang Tu ◽  
...  

2005 ◽  
Vol 2005 (3) ◽  
pp. 171-172 ◽  
Author(s):  
Min Zhang ◽  
Yi-Qun Li

Aromatic aldehydes can be converted into the corresponding 1,1-diacetates rapidly in the presence of catalytic amounts of Ce(SO4)2·4H2O at room temperature in excellent yield under solvent-free conditions. The catalyst can easily be recovered and reused at least 4 times.


2005 ◽  
Vol 83 (5) ◽  
pp. 505-507 ◽  
Author(s):  
Najmodin Azizi ◽  
Mohammad R Saidi

Lithium perchlorate catalyzed the ring opening of epoxides with amines to provide the corresponding β-aminoalcohols in excellent yields with high regioselectivity. The reaction proceeds rapidly under mild and neutral conditions and worked well with primary, secondary, aliphatic, aromatic, and hindered amines in short times at room temperature, in the absence of solvent.Key words: epoxide, lithium perchlorate, β-aminoalcohols, solvent-free.


2019 ◽  
Vol 31 (6) ◽  
pp. 1357-1361 ◽  
Author(s):  
NARENDRA R. KAMBLE ◽  
VINOD T. KAMBLE

A combinatorial library of benzylpyrazolyl coumarin derivatives have been synthesized by a green one-pot four-component reaction between aryl hydrazine/hydrazine hydrate (1), ethyl acetoacetate (2), aromatic aldehydes (3) and 4-hydroxycoumarin (4) catalyzed by niobium pentachloride with silver salt under solvent-free conditions has been developed. Experimental simplicity, simple work-up procedure and solvent-free reaction condition at room temperature are important features of the present protocol.


2020 ◽  
Vol 50 (10) ◽  
pp. 1545-1560 ◽  
Author(s):  
Gurpreet Kaur ◽  
Mussarat Shamim ◽  
Vaishali Bhardwaj ◽  
Vivek Kumar Gupta ◽  
Bubun Banerjee

RSC Advances ◽  
2016 ◽  
Vol 6 (59) ◽  
pp. 54236-54240 ◽  
Author(s):  
Seyed Mohsen Sadeghzadeh

A green and efficient method for the synthesis of various triazolo[1,2-a]indazoletrione under mild conditions is reported, that making it a genuinely green protocol.


ChemInform ◽  
2011 ◽  
Vol 42 (21) ◽  
pp. no-no
Author(s):  
Parvin Kumar ◽  
Sunil Kumar ◽  
Khalid Husain ◽  
Ashwani Kumar

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