my product is 5-bromo-2-(4-nitro-1H-pyrazol-3-yl)-1H-benzoimidaole. I used EDC and HoBt in DMF then I did reflux for 12 hours with glacial AcoH.
I got very dark glue like crude.
I think you can do a work up with ethyl acetate and water. You have to do it several times. I believe, your product will come into the organic layer while EDC, HoBt, DMF etc would go into water. You must first do the work up in a small scale (like in a sample vial) and check the TLC for your product. I hope this helps.
you will be seperat your product by solvent extraction method. first run the TLC & the clear spot of product is identified by running different solvent system. then check the location of of the of final product that it is at top area of TLC or at bottom side of TLC.
then according Spot location
1. at top area :- use slightly polar solvent, like benzene, toluene.
2. at bottom side:- use highly polar solvent, like ethyl acetate, MeOH, EtOH.
then treat the final compound with suitable solvent. and seperate the final compound by evaporation of the solvent...
I could not understand why you used DMF, however pour the reaction mixture n plenty of water; filter dry and crystallize from rectified spirit.
Hi, try to dissolve your glue in the minimum amount of MeOH and then add water under vigorous stirring.
If you get a fine solid filter it off and ceck if it is pure enough for you. Alternatively try a work up as suggested above (ceck that the mixture is fully soluble in AcOEt or DCM) and then recover your pure product from the organic layer with eiter:
1. FCC (use an eluent in which your material is reasonably soluble and that gives you an Rf ~ 0.3 on TLC)
2. crystallization (try medium polarity solvents like iso-propyl ether or ethyl acetate/hexane mixtures)
3. If you've got access to reverse phase FCC just dissolve the glue in the minimum amount of DMSO and purify it with a gradient 100% water to 100% ACN
Good luck
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