problem in chalcone synthesis.pdf
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6/25/2015 Problem in chalcone synthesis. ResearchGate
http://www.researchgate.net/post/Problem_in_chalcone_synthesis2 1/3
Ramón JEstévez
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MilagrosAvendaño
BrajeshKumar
Ramón JEstévez
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Ramón J Estévez · University of Santiago de Compostela
I don't kow your reaction conditions. In my opinion basic conditions arenot a good choice, because the phenolic groups are probably convertedinto the corresponding phenoxy groups and this could dramaticallyreduce the basic character of the protons in alfa position to the cabonylgroup.We have prepared some chalcone related compounds using ammoniumacetate/acetic acid mixtures. Try to use the following proportions:chalcone (0.66 mmol), aldehyde (0.66 mmol), NH4OAc (1.46 mmol) andAcOH (6 mL).
May 27, 2013
Milagros Avendaño · Central University of Venezuela
Hi, I noticed that you do not specify the reactive agents you are using. Ifyou are working in a basic medium take in account that youracetophenone reactant has two phenol groups which are acidic. Maybethat is what’s troubling you
May 27, 2013
Brajesh Kumar · Escuela Politécnica del Ejército
You are using 2, 4 dihydroxy acetophenone and other benzaldehyde inbasic condition (NaOH in Methanol), Try to reduce the volume afterpreperation of Chalcone and keep in refrigerator for overnight, Chalconemust precipitate. Becoz, dihydroxy chalcone are highly soluble inmethanol/ water mixture.
May 27, 2013
Ramón J Estévez · University of Santiago de Compostela
I don't kow your reaction conditions. In my opinion basic conditions arenot a good choice, because the phenolic groups are probably convertedinto the corresponding phenoxy groups and this could dramaticallyreduce the basic character of the protons in alfa position to the cabonylgroup.We have prepared some chalcone related compounds using ammonium
Umangkumar Harishchandra ShahCharotar University of Science and Technology
2 / 1
Problem in chalcone synthesis.
In a part of my research, I am synthesizing a chalcone from 24dihydroxyacetophenone and various benzaldehyde derivatives. I am following yourprocedure published in article but I could not get the success in the reactions soplease help me.
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May 27, 2013
Chalcones
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6/25/2015 Problem in chalcone synthesis. ResearchGate
http://www.researchgate.net/post/Problem_in_chalcone_synthesis2 2/3
JamesSherwood
Sameralihasan
Sameralihasan
acetate/acetic acid mixtures. Try to use the following proportions:chalcone (0.66 mmol), aldehyde (0.66 mmol), NH4OAc (1.46 mmol) andAcOH (6 mL).
May 27, 2013
James Sherwood · The University of York
Acid catalysis is the way to go! Any strong acid should work (12 mol%).No solvent is needed if you're using at least one liquid reactant, stirringat 100120 C, no special atmosphere are drying required. Cool down forprecipitation of the product.
May 28, 2013
Krishnasarma pathy/ SARMA KRISHNA PATHY · IPL LTD
Providing various methods of experimental process followed forpreparing chalcone Solution phase conventional method:A mixture of 2, 4dihydroxy acetophenone (0.01 mol) and aryl aldehydes(0.01 mol) wasstirred in ethanol (30 mL) and then an aqueous solution of KOH (40%,15 mL) was added to it. The reaction mixture was kept overnight at roomtemperature and then it was poured in to crushed ice and acidified withHCl. The solid separated was filtered and recrystallizedfrom ethanol Solid phase microwave method:To a solution of 2, 4dihydroxyacetophenone (0.01 mol) and substitutedaromatic aldehyde(0.01mol) in DMF (5mL) taken in 100 mL borosil flask,was added montmorrilonite K 10clay (4g). The mixture was uniformlymixed with glass rod and air dried to remove thesolvent. Adsorbedmaterial was irradiated inside a microwave oven for specified timemedium power level (600 W). After the completion of the reaction(monitored by TLC), the reaction mixture was cooled at roomtemperature and the product was extracted with ethanol (2 x 20 mL).Removal of the solvent and subsequent recrystallisation with ethanol
May 28, 2013
Hassan Faidallah · King Abdulaziz University
you may need to acidify with 20% HCl after pouring in water since youhave to acidic OH
May 28, 2013
Dr. Amit Tapas · Sudhakarrao Naik Institute of Pharmacy
First try to protect the hydroxyl group with DMS or Benzoyl Chloride orother protecting group (information you will get from literature). Thencarry out the reaction of protected dihydroxyacetophenone with suitablearomatic aldehyde. Protection is must since phenolic hydroxyl group aremuch reactive.
Jun 7, 2013
Samer ali hasan · University Of Kufa
Using thionyl chloride in ethanol as a catalyst will avoid any problems inthe chalcone synthesis as hydroxyl group which not need to protection
Aug 14, 2013
Samer ali hasan · University Of Kufa
follow my procedure in my article and you will get your target
SYNTHESIS OF NEW FLUORINATED CHALCONE DERIVATIVE WITHANTIINFLAMMATORY ACTIVITY
Aug 14, 2013
1s2.0S0040403902009905main1.pdf
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6/25/2015 Problem in chalcone synthesis. ResearchGate
http://www.researchgate.net/post/Problem_in_chalcone_synthesis2 3/3
HassanFawzyMadkour
Fathi Aqra · Hebron University
See this article:Rajender S. Varma, Manju Varma,Monatshefte für Chemie / Chemical MonthlyDecember 1982, Volume 113, Issue 12, pp 14691473
Dec 27, 2013
Madhukar Baburao Deshmukh · Shivaji University, Kolhapur
React 2,4dihydroxy acetophenone with benzaldehyde in presence ofNaoH stirr the reaction mix. with cooling, the chalcone separates out .
May 31, 2014
Hassan Fawzy Madkour · Ain Shams University
Please kindly read the following article to find the solution of yourproblem:
Analele Universităţii din Bucuresti – Chimie (serie nouă), vol 20 no. 1,pag. 15 – 24
K.L. Ameta , Nitu S. Rathore and Biresh Kumar
Good luck.
Mar 27, 2015
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