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list of experiments
Solubility book (3rd Edn)
solubility nmr 3
To determine solubility of 3,4-(methylenedioxy)phenylacetic acid in different solvents, including chlorobenzene, chloroform, methanol, acetonitrile, ethanol, 1,2-dichloroethane, THF, toulene, dichloromethane, ethylbenzene, benzene, DMF, DMSO, and 1,4-dioxane.
We filled half-dram vials with different solvents, then added the solute 3,4-(methylenedioxy)phenylacetic acid to each vial until the solution appeared to be saturated. Then we parafilmeed and vortexed the samples and heated them in a bath to make sure they were fully saturated. We cooled the samples to room temperature of about 23 deegrees Celcius and took NMRs, using SAMS to determine solubility at room temperature.
(all 3 pictures were taken immediately after the vials were taken out of the bath)
[Many of the spectra don't match the stated solvent and solute - identify which are correct and fix the ranges JCB]
most samples appear to be contaminated, with some something else (possibly glycol-water), these samples are colored orange and marked DONOTUSE-
[Go through each spectrum and confirm that all the peaks are accounted for with no extra peaks JCB]
The concentration from the methanol spectra matches closely to the concentration obtained from
[You have the NMRs - is there a reason that you can't use at least some of the numbers? JCB]
I think the number obtained from the NMRs I do have are usable.
[Identify which solubilities are valid (NMRs consistent with solute/solvent) and add to SolSum sheet JCB]
14:44-12 solvents added to 12 half-dram vials 300microliters each
14:51-added solute to vial 1, using spatula and wax paper. tightly capped and parafilm, vortexed to get a rough idea of saturation.
1520-repeated to vials 2-11. 12 is discarded as it is no longer needed.
I don't know.
1541-prepared capped and parafilmed samples 13-15. See spreadsheet.
1605-tagged samples are placed in 40 degree Celcius bath.
1900-bath temperature is changed to 23 degrees.actual bath temperature is 40 degrees.
1430-removed samples from bath. bath temperature is 22.5 degrees.
1545-removed supernatant from samples 3-5 and combined with D-chloroform in NMR tubes. sample 2 appears to have 2 layers. sample 1 contains no liquid.supernatant was transferred immediately after it was removed from the the bath.
1630-did the same with samples 7, 8 and 11.
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