Researcher

Khalid Mirza

Objective

To synthesize 28 Ugi products via a 4 component Ugi reaction. These reactions have been predicted to form a solid Ugi product at 0.5M concentration of each component in methanol at a probability of 60-70%. [link JCB] The results will serve to improve the model.

Procedure

To twenty eight labeled vials, calculated volume of methanol was added. Following methanol addition an aldehyde, a primary amine, a mono-carboxylic acid and an isocyanide (0.1mmo each) was added. The final volume of the reaction mixtures was set to 200uL (assuming volumes are additive). This was done to ensure the final concentration of each component in the reaction mixture was 0.5M. After the addition of the chemicals, vals were tightly screw-capped and left overnight for the reactions to complete.
After 24h vials were checked for solid formation and the results were recorded to facilitate the construction of a model to predict the formation of solid Ugi product with in 24h from a 4 component Ugi reaction.

Results

UCExp236 -Spreadsheet

UCExp236-7A
HNMR
CNMR
MS
IR
Mpt

Discussion

Conclusion


Log

2009-07-06

18:00 Made-up 2M solutions of 3,3'-dichloropivalic acid, formic acid and methacrylic acid (1mL )by dissolving 2mmols of each acid in methanol in a 1mL volumetric flask.
Acid
Quantity dissolved
in methanol to make
a 2M solution
3,3'-dichloropivalic acid
342.4mg
formic acid
76.0uL
methacrylic acid
170uL
18:30 Labeled 28 vials from 1-29 (excluding 6).
19:00 Pipetted out appropriate volume of methanol in to each vial (see UCExp236 -Spreadsheet)
19:40 Pipetted out aldehyde in to the vials.
20:20 Addition of amine followed the aldehyde addition.
21:00 Transferred acid in to the vials....soon after the completion of acid addition to vials....vials 1, 22 and 27 developed crystalline needles, which did not dissolve even after vortexing for 30s each.
21:30 Isocyanides were then pipetted out in to all vials.
21:50 After the addition of isocyanides. all the vials were vortexed for 30s each. VIal #1 , 22 and 27 still contained white crystals.
22:10 Left the vials at room temperature for the reactions to complete.

2009-07-07

10:00 Vial #7 has turned in to a solid mass.
10:45 Vortexed each vial for 30s and left them back on the bench. Vials 1, 22 and 27 still contained the solids observed last night.
14:00 To the vial containing the solid mass, methanol (200uL) was added, vortexed for 1min to mix the contents thoroughly. The solution was centrifuged and the supernatant was decanted away. The residue was washed further with methanol (2x 200uL), centrifuged and the residue finally obtained was left in a vacuum desiccator to dry off the solvent traces.
18:00 Obtained 24mg of a white, dry shiny powder (from vial#7). This is now labeled UCExp236-7A
18:30 Obtained an HNMR of UCExp236-7; yield -47%.