Researcher

Evan Curtin

Objective

To determine the solubility of four imines: salicylideneaniline (1), N,N-dimethyl-4-[(E)-(phenylimino)methyl]aniline (2) and N-(4-methoxybenzylidene)aniline (3) from UCexp269 and N-vanillylidene aniline (4) from UCexp268 in methanol(1), ethanol(2), acetonitrile(3), THF(4) and toluene(5).

Procedure

Each imine was mixed with each solvent and heated to 50C. The resulting mixtures were decanted when necessary to obtain a solution at 50C. The solutions were allowed to cool at RT until precipitate formed. In the case where no precipitate formed, the solution was evaporated slowly using blown air until precipitate formed. The supernatants were then isolated and an HNMR spectra of each solution was obtained. By integrating the peaks, the concentration of the solute was found.

Results

SAMS2 (N,N-dimethyl-4-[(E)-(phenylimino)methyl]aniline)
SAMS3 (N-(4-methoxybenzylidene)aniline)
SAMS4 (N-vanillylidene aniline)

Solubility Chart (link) :

Discussion

Imine 1 (salicylideneaniline) proved difficult to produce a supernatant that was easily isolatable. As a result, no measurements were made for that imine.

Conclusion

Solubility in each of the solvents was found for compounds 2, 3 and 4. The experiment will need to be repeated for salicylideneaniline.

Log

2011-08-02

11:48 - Put roughly 200mg of each imine into 1 dram screw cap vials, each labeled with two numbers. The first number represents the imine and the second is the solvent.
12:24 - Added 200-300 microliters of solvent to each sample. Samples 1-3, 1-4, 1-5, 3-4, 3-3, and 2-4 all dissolved completely. Added more imine to these samples until solid remained in the mixture.
12:39 - Parafilmed each sample.
13:43 - Heated samples in a 50C bath. All samples with imine #1 or #3 dissolved within 10 seconds. In addition, samples 2-3, 2-4, and 2-5 dissolved within one minute. None of the samples of imine #4 along with samples 2-1 and 2-2 dissolved completely .
14:13 - Added 2mL toluene to sample 4-5, sample did not dissolve completely after sonication and heating in 50C bath.
14:25 - Added 1mL THF to sample 4-4, it dissolved completely.
14:25 - Added 2mL of MeOH to samples 2-1 and 4-1, 2mL of EtOH to samples 2-2 and 4-2, and 2mL of acetonitrile to sample 4-3, none of these fully dissolved at RT (24C).
14:43 - Heated 2-1 and 2-2, both dissolved in 1 minute.
14:52 - Placed 4-1, 4-2, 4-3, and 4-5 in 48C bath.
14:54 - samples 2-3, 2-4, 2-5, and 3-5 all formed precipitate (where there was no solid before). Slowly blew air on the other samples (1 to 2 seconds of air followed by several seconds standing at RT) until precipitate formed in all samples except those containing imine #1 and 4-1, 4-2, 4-3, and 4-5.
15:37 - Removed 4-1, 4-2, 4-3 and 4-5 from 48C bath, decanting immediately into 1 dram push cap vials. All of these samples formed precipitate after sonication.
16:19 - Blew air on 1-2 until ~100 microliters of liquid remained. Observed layers of solution and a somewhat viscous liquid. Let all samples sit at RT.
17:02 - Took supernatant from samples of imine #2, added CDCl3 and put in NMR tube.
17:15 - Took HNMR of samples 2-1, 2-2, 2-3, 2-4, and 2-5 using 500MHz varian NMR.

2011-08-4

9:56 - Added CDCl3 to samples of imine #3 and #4
10:19 - Put CDCl3 solutions in NMR tube.
11:05 - Took HNMR using 500MHz varian NMR.