I tried molecular sieve 3A but actually it did not work.,My reaction is very sensitive water environment .Thanks
DEAR Cahit Can Çanakçı
read attached book
Deuterated Solvents for NMR • NMR Solvents • NMR Reference Standards • NMR Tubes
Dear Cahit Can Çanakçı you can dry your DMSO-d6 over calcium hydride (CaH2), followed by distillation. See also this earlier thread on RG concerning the same question:
https://www.researchgate.net/post/What_is_the_best_way_to_dry_DMSO_Are_molecular_sieves_enough
Stirring it over calcium hydride and vacuum distillation is the only way to get rid of water, and after distillation you have to put it over 4A molecular sieves for atleast 24 hour, then only you can water free DMSO-d6. I know this process is very costly but this is the only way.
Cahit Can Çanakçı I agree with David Dayanidhi in that using molecular sieves is easier. However, as rajeev chand Nishad pointed out, calcium hydride is more effective in removing the last traces of water.
In general, most of the dry solvents, and specially DMSO, are quite hygroscopic in nature.
If you are handling moisture sensitive compounds, you may carry out all transfers of samples and the dry solvent inside a dry-box.
With best wishes.
Ashis Ranjan Bandyopadhyay I fully agree with Ashis Ranjan Bandyopadhyay in that, after drying, the DMSO-d6 is hygroscopic and must be stored either in a Schlenk flask or inside a dry-box.
Use high pressure vaccum pump continuesly until complete dryness and immediately perform NMR experiment
Calcium hydride removal of water is an ideal way to remove water, but the resulting solid impurities are more difficult to remove. It is recommended to use sodium block to remove water, which can reduce the water content to about 10ppm.@@@
Cahit Can Çanakçı and Guangcong Wan sodium metal is NOT suitable for drying DMSO-d6 as it is known that sodium or potassium react with DMSO!
Article The Reaction of Sodium and Potassium with Dimethyl Sulfoxide...
Vedhanayagam Mohan if you use a high pressure vacuum pump until complete dryness, all the DMSO-d6 will be gone into the cold trap...😎
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