Researcher

Hai Truong & Khalid

Objective

To measure the solubility of UC176C in a 0.1M imine solution in benzene b) 0.1M n-butylisocyanide solution in benzene

Procedure

A) Make-up a 0.1M molar imine solution in benzene by dissolving phenanthrene-9-carbaldehyde (0.1mmol, 21mg, 17uL) in benzene (974uL). To this add fufurylamine (0.1mmol, 9uL). Solution
Total volume 17+974+9 = 1000uL
Concentration per component = 0.1M
If the reaction goes to 100% conc of imine =0.1M
B) Dissolve n-butylisocyanide (0.1mmol, 10.4uL) in benzene (989.6uL) to make a 0.1M solution.
C) Pipette out 200uL of A in to a half dram vial add the Ugi product.



Results

Spreadsheet ONSCExp148-i

Discussion


Sample ID
Ugi conc(M)
aldehyde conc(M) SAMS estimate
amine conc (M) SAMS estimate
imine conc (M)SAMS estimate
aldehyde at start (SAMS) (M) (aldehyde+imine)
amine at start (SAMS) (M)
(amine+imine)
% aldeyde
xs
ONSCExp148-1A
0.03
0.04
0.02
0.04
0.08
0.06
33.33
For sample ONSCExp148-2A with n-butylisocyanide as co-solute, the HNMR shows an overlap of the methyl from the Ugi product 176C with the methyl from isocyanide. Therefore to calculate the integral for just the Ugi product, solute integral for isocyanide was subtracted from the total integral for Ugi product plus isocyanide.Using the resultant integral gave 0.07M as the solubility of the Ugi product in 0.06M butyl isocyanide in benzene.

Since aldehyde to amine ratio used in this experiment was inequal, this experiment would have to be repeated.
Also, it would be appropriate to re-confirm the affect of isocyanide on the solubility of Ugi product in benzene.
In future, atleast 400-500uL of supernatant must be used to obtain HNMRs. This should significantly enhance the signal to noise ratio and improve the accuracy of the results.

Conclusion

This experiment is best repeated with more accurate micropipettors, so as to measure equimolar volume of amine relative to aldehyde.

Log

2009-11-10
15:15 Prepared the first solvent by putting 21mg phenanthrene-9-carbaldehyde + 974uL benzene + 9uL fufurylamine into a dram vial. Labeled A. The concentration of solvent was 0.1M imine in benzene.
15:30 Prepared the second solvent by putting 10.4uL n-butylisocyanide + 989.6ul benzene to make 0.1M solution. Labeled B.
15:00 Took out 2 half dram vials. Labeled Exp148-01, Exp 148_02:
For vial Exp148-01: put 200ul solvent A and a small amount of UC176C. The solid still remained after vortexing.
For vial Exp148-02: put 200uLsolvent B and a small amount of UC176C. The solid still remained after vortexing.
17:10 Parafilmed both Exp148-01 and Exp148-02.
17:15 Put them into the Laura heating/cooling bath. The temperature in the path at this time was 40C
17:45 Adjusted the temperature in the bath down to 25C.
18:10 The temperature in the bath was 25C.
19:15 Removed the vials from the temperature control bath.
19:25 Centrifuged the vials.
19:45 Carefully pipetted-out approximately 100uL of the supernatant from each vial and transferred then in to one dram vial containing 300uL DMSO-d6. The one dram vials were labeled ONSCExp148-1A, ONSCExp148-2A
20:10 Completed obtaining HNMRs.