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Solubility book (3rd Edn)
To determine the solubility of Phenanthrene-9-carboxaldehyde, 1-pyrenebutyric acid and piperonal in different solvents at 25C by NMR spectroscopy using an acetonitrile as an internal standard.
Saturated solution of pheanthrene-9-carboxaldehyde was prepared in benzene and 1,1,2-trichlorotrifluoroethane. Saturated solution of 1-pyrenebutyric acid were also prepared in benzene, 1,2-dichlorobenzene, methylene chloride, tetrahydrofuran, methanol, dimethylsulfoxide and 1,1,2-trichlorotrifluoroethane. Similarly methanol was saturated with piperonal. After setting them for equilibrating for 5h, 100uL of the saturated solution was dissolved in CDCl3 in NMR tubes. Acetonitrile (10uL) was added to each NMR tube as an internal standard. Proton NMR was obtained for each sample. Concentration of saturated solution was calculated by comparing the integrations for the peaks of the solute with that of acetonitrile (2.0 ppm).
[I think you did a good job with reporting the analysis in the spreadsheet - to wrap up just report on the numbers where you are confident (and add to SolubilitySum) and how they compare with other measurements from other ONS experiments and the literature if applicable JCB]
While integrating the peaks it is assumed that the proton (used) has relaxed completely. This hypothesis would be put to test in the next experiment when spectrum of same sample will recorded with variable relaxation times inorder to compare peak integrations.
spreadsheet analysis, solubility of piperonal in methanol is determined to be 8.11M
SAMS Piperonal analysis
[Why is only one compound included in the SAMS analysis? JCB]
14:00 Prepared saturated solutions of 9-phenanthrene carboxaldehyde in benzene and 1,1,2-trifluorotrichloroethane. Saturated solutions of 1-pyrenebutyric acid were also prepared in benzene, 1,2-dichlorobenzene, methylenechloride, THF and methanol. Each solution was vortexed for 3-5 min.
19:00 After equlibrating the saturted solutions for five hours vials # 3 and # 4 had the solute still suspended in the solvent.
19:30 All vials were centrifuged for 3 min. Vials # 3 and # 4, solute still did not settle down..therefore no supernatant could be obtained for these 1-pyrenebutyric acid in 1,2-dichlorobenzene and dichloromethane.
19:45 From each vial 100uL of the supernatant was transferred in to clean dry NMR tubes (vials # 3 and # 4 discarded).
20:00 Added CDCl3 (700uL) to each tube, also acetonitrile (10uL) was added to each one. The NMR tube containing 1-pyrenebutyric acid in DMSO precipated out once chloroform-D was added.
22:00 Obtained HNMR of sample on a Varian Unity Inova-500MHz instrument.
11:00 Prepared a saturated solution of piperonal in methanol by vortexing it for 10min. The solution was left undisturbed to equlibrate.
14:20 After equilibration the supernatant was transferred to another vial.
14:40 From the supernatant 100uL was transferred to an NMR tube, CDCl3 (700uL) and acetonitrile (10uL) was added to it.
15:00 Obtained HNMR of the sample on the Varian Unity Inova 500MHz instrument.
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