Can I use DMF as a solvent for DCC coupling between acid and phenol?
Dear Ms. Sasidharan
In response to the your question, it should be mentioned that if the yield of the reaction is good, using dry solvents with lower boiling points such as dry acetone under reflux in the presence of an acidic catalyst is better and leads to easy separation and purification of obtained products by Dean-Stark method, otherwise, the use of toluene is better way than DMF because leads to facile purification of obtained products by above given conditions. At end, if your products are liquid and have low b.p, in this case you can use DMF as solvent without having any issue for separation and purification of products.
With the best wishes
More common is to use DCM, THF or acetone or something like that but
Steunenberg, Peter; Ruggi, Albert; Van Den Berg, Nynke S.; Buckle, Tessa; Kuil, Joeri; Van Leeuwen, Fijs W.B.; Velders, Aldrik H.
Inorganic Chemistry, 2012 , vol. 51, # 4 p. 2105 - 2114
did indeed use DMF for the coupling.
Also
Biela, Adam; Nasief, Nader N.; Betz, Michael; Heine, Andreas; Hangauer, David; Klebe, Gerhard
Angewandte Chemie - International Edition, 2013 , vol. 52, # 6 p. 1822 - 1828
Riches, Andrew G.; Cablewski, Teresa; Glattauer, Veronica; Thissen, Helmut; Meagher, Laurence
Tetrahedron, 2012 , vol. 68, # 46 p. 9448 - 9455,8
There are a lot of procedures in the literature, so it is possible but probably not the easiest way :)
BW
Most common solvent for this Steglich esterification is dichloromethane. In case your substrates are sparingly soluble in dichloromethane, you can DMF as solvent. There are reactions reported in DMF as well.
B. Neises, W. Steglich, Angew. Chem. Int. Ed., 1978, 17, 522-524.
It should work, though people usually prefer a solvent which is easier to evaporate after the reaction is complete.I suggest you use it only if your reactants are not soluble in other solvents llike DCM or THF.
Also, phenols aren't good nucleophile, you can add a catalytic amount of DMAP to help your reaction.
More info: http://www.organic-chemistry.org/namedreactions/steglich-esterification.shtm
DCC is a potent allergen and sensitizer, and the ureas are often difficult to remove completely. Consider using tripropyl phosphonic anhydride (T3P); its side products are water-soluble, and it is very effective at this type of coupling.
It is commonly sold as a solution in DMF.
DMF is suitable, but It should be dried. Mixture of 1000 ml DMF and 150-200 ml toluene distilled with a reflux condenser or use DMF extra dry grade.
DMF should work. This reaction will be sensitive to dimethyl amine that is a breakdown product of DMF. As suggested previously, please make sure that you use a high grade of dry solvent and you may even want to activate 3 Angstrom molecular sieves at >160 degrees C and place in a desiccator while hot over fresh P2O5 and under vacuum until cool. The activated sieves will absorb any free amine prior to use. I have used pyridine for DCC couplings and it is a good solvent if polarity is needed for solubility as opposed to some of the standard DCC coupling solvents. DMAC is also a less reactive alternative solvent although slightly higher boiling than DMF.
Hello, Sasidharan!
Just as Shiv said, DMF removal as well as the by-product, DCU will be a great challenge for you if you use DMF for Steglish esterifcation.
The common practice is to use DCM since DCU can be removed by filtering the reaction mixture through a pad of celite and rinsing with a minimal amount of reaction solvent before work up and removal of the rest straightway by flash chromatography.. However, if it is too soluble, one can as well concentrate the reaction mixture first and take it up in ether, before filtering and rinsing.
Nevertheless, acetonitrile or carbon tetrachloride are good alternative solvents as dicyclohexyl urea is much less soluble in them than in DCM or chloroform.
Good luck
i just want to couple dopamine with ferrocence carboxylic acid.So could any body tell me about the condition of temperature ,solvent and catalyst for a good yield.
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