Objective

To synthesize three dipeptides via a 4 component reaction in THF and DMSO at 0.5M and 1M concentration per component, if possible.

Procedure


Results

Picture
UCExp222-1
UCExp222-2
UCExp222-3
HNMR
222-1A
222-2A
222-4A
Spreadsheet


Discussion

Solid precipitates were obtained for the reactions involving benzaldehyde, furfurylamine, boc-glycine and t-butylisocyanide in DMSO at 1M concentration per component,

Conclusion

Solid products were obtained only for the reactions involving benzaldehyde, furfurylamine, boc-glycine and t-butylisocyanide in DMSO at 1M; however reactions involving 1-pyrenebutyric acid yielded no solid Ugi products in THF.

Log

2009-05-15

13:00 Labeled six one dram vials 222-1, 222-2, 222-3, 222-4, 222-5 and 222-6
15:20 In vial 222-1 pipetted-out 273uL DMSO, followed by benzaldehyde (0.5mmol, 50.7uL), furfurylamine, (0.5mmol, 44.2uL), boc-gly (0.5mmol, 87.6mg), and finally added t-butylisocyanide (0.5mmol, 56.5uL). After each addition the solution was vortexed for about 15s.
15:40 In vial 222-2 pipetted-out 273uL THF, followed by benzaldehyde (0.5mmol, 50.7uL), furfurylamine, (0.5mmol, 44.2uL), boc-gly (0.5mmol, 87.6mg), and finally added (t-butylisocyanide 0.5mmol, 56.5uL). After each addition the solution was vortexed for about 15s.
16:00 In vial 222-3 pipetted-out 136.5uL DMSO, followed by benzaldehyde (0.25mmol, 25.4uL), furfurylamine, (0.25mmol, 22.1uL), boc-gly (0.25mmol, 43.8mg), and finally added (t-butylisocyanide 0.25mmol, 28.3uL). After each addition the solution was vortexed for about 15s.
16:30 In vial 222-4 pipetted-out 136.5uL THF, followed by benzaldehyde (0.25mmol, 25.4uL), furfurylamine, (0.25mmol, 22.1uL), boc-gly (0.25mmol, 43.8mg), and finally added (t-butylisocyanide 0.25mmol, 28.3uL). After each addition the solution was vortexed for about 15s.
17:00 In vial 222-5 placed 4-(dimethylamino)benzaldehyde (0.5mmol, 74.6mg), methylamine (0.5mmol, 250uL of 2M solution in THF), 4-pyrenebutanoic acid (0.5mmol, 144.1mg), t-butyl isocyanide (0.5mmol, 56.5uL), and finally added THF 11.9uL.....This solution had readily dissolved all the components...a homogeneous solution was obtained. After each addition the solution was vortexed for about 15s.
17:45 In vial 222-6 placed p-tolualdehyde (0.5mmol, 58.9mg), methylamine (0.5mmol, 250uL of 2M solution in THF), 4-pyrenebutanoic acid (0.5mmol, 144.1mg). After each addition the solution was vortexed for about 15s, however the solution did not dissolve the acid...hence another THF (223uL) was added and vortexed for 10s, when the solution became homogeneous...this is when t-butylisocyanide (0.5mmol, 56.5uL) was added and further vortexed for 15s.
18:30 Obtained a picture of the vials containing the reaction mixtures...picture UCExp222-1

2009-05-16

18:45 Obtained a picture of the reaction mixture vials. (Picture UCExp222-2)Vials 222-1, 222-3 and vial number 222-4 had developed some solid in them. Vials 222-2 and 222-4 containing solid appeared almost dry, this was inspite of being tightly capped.
19:00 Vortexed vial 222-1 and centrifuged for 2min and decanted off the supernatant.
19:10 Washed the solid in vial 222-1 with DMSO, 500uL x 3..each time vortexing it for 30s, centrifuging the solution for 2min and finally decanting supernatant..
19:30 To remove DMSO from the solution ( in vial 222-1), it was washed another three times with methanol (500uL) as was done with DMSO previously.
20:00 Similarly solids in vials 222-2 and 222-4 was washed with THF (500ul x 3)...
20:45 A picture of vials 222-1, 222-2 and 222-4 containing the residue after washing with solvents was obtained....(picture UCExp222-3)
20:55 The vial were left uncapped in a desiccator connected to house vac.

2009-05-18

13:00 After drying the sample obtained 222-1A (90.6mg), 222-2A (84.2mg) and 222-4A (37.8mg)
14:30 Obtained HNMRs of 222-1A, 222-2A and 222-4A by dissolving the samples in CDCl3