Sciencemadness Discussion Board

pyrrolidinyl-cyclohexyl-carbonitrile does not stay crystallize

busybird - 12-10-2014 at 14:33

126g of sodium bisulfite was dissolved in 420 mL of H2O. 106 g of cyclohexanone was added with vigorous stirring. The bisulfite adduct formed immediately as a thick white slurry. The slurry was then cooled with an ice bath, and a solution of 78.6g KCN and 94.8 g pyrrolidine was added. After stirring overnight at room temperature followed by cooling in an ice bath, the PCC did not crystallize. So stirred it vigorously and it did crystallize but the crystals melt at room temp. So I let the crystals melt dissolved it with hexanes, dried with sodium sulfate, and evaporated the solvent in a roto-vap but same as before.

I would just like to keep the crystals . Does anyone have any advice?

[Edited on 12-10-2014 by busybird]

forgottenpassword - 12-10-2014 at 15:04

I have a similar problem with my water crystals.

skip - 18-7-2015 at 05:37

I know this topic is quite old. I would like to add information for future reference. When pyrrolidine is used , no crystals form. Its a yellow, clear oil isolated by extraction and not filtration. The final comp. is not even worth the cost or trouble.