Skip to main content
Get your brand new Wikispaces Classroom now
and do "back to school" in style.
Pages and Files
UC on ChemSpider
Alicia's Masters Thesis
Open Web Drug Dev.
To Do List
Ugi NMR Analysis
Ugi product 1
Ugi product 2
To synthesis Ugi products using a) formaldehyde (paraformaldehyde), methyl amine, formic acid and t-butylisocyanide; b) formaldehyde (paraformaldehyde), methyl amine and n-butylisocyanide in methanol
Procedure using 1,3-5-trioxane
A solution of 1,3,5-trioxane (2mmol, 180mg) is dissolved in methylamine 2M in methanol (6mmol, 3mL) and formic acid (6mmol, 226uL). To one half of this three component solution (1.5mL) 1-butylisocyanide (3mmol,313uL) was added and to the remaining three component solution (1.5mL) t-butylisocyanide (1.5mmol, 340uL) was added. the two reactions were then left over night for the Ugi product precipitation.
Procedure using paraformaldehyde
A solution of paraformaldehyde (10mmol, 300mg), in 2M methyl amine in methanol (10mmol, 5mL) and formic acid (10mmol, 377uL) was prepared in a 2 dram vial. The solution was vortexed to ensure complete dissolution of the reagents. To one half of the three component solution (2.5mL) 1-butylisocyanide (5mmol, 523uL) was added and the to the remaining three component solution (2.5mL) t-butylisocyanide (5mmol, 565.5uL) was added. The two reaction mixtures were then left over night for the Ugi product precipitation.
Show Header Information
Show Header Information
[You could also try aqueous formaldehyde, which worked fine with an excess
17:00 Pipetted out methylamine (10mmol, 5mL, 2M in methanol) in to a glass vial, added paraformaldehyde (300mg=10mmol formaldehyde) to vial. Paraformaldehyde was obtained as a very fine white powder. It did not dissolve completely in to the methylamine/methanol solution. Vortexed the solution, yet was unable to dissolve it completely.
17:10 Pipetted out formic acid (10mmol, 377uL) in to the above solution. Vortexed it. The vial turned hot. The paraformaldehyde powder did not dissolve completely yet.
17:15 Set the vial to sonicate with the bath at room temperature.
18:17 Paraformaldehyde still insoluble in the reaction mixture.
18:20 Going to try the reactions with 1,3,5-trioxane.
18:30 Made-up a solution of 1,3,5-trioxane (6mmol, 180mg), methylamine (6mmol, 3mL, 2M solution in methanol) and formic acid (6mmol, 226uL) in a glass vial.
18:40 Pipetted out 1.5mL of this three component solution into another glass vial. To this solution added n-butyl isocyanide (3mmol, 313uL) and vortexed the resulting solution. This solution is labeled
. Note: n-butylisocyanide appears to have gone bad, when purchased it was a clear solution, now it has turned brick red..no change in its odor.
[Hard to tell from color how much impurity present - it would be worth taking NMR of the isonitrile to see if it is at least >95% pure JCB]
18:45 To the remaining 1.5mL three component solution added t-butylisocyanide (3mmol, 340uL) and vortexed the resulting clear solution.
[The clear solution at this point is the key - not the ability to make up a 2M solution of paraformaldehyde in methanol JCB]
This solution is labeled
18:50 Left the solution in the hood for the reaction to complete.
13:00 No solid has precipitated out in either solutions.
[It might be worth taking an NMR of the crude mixture just to see if any Ugi product formed JCB]
20:10 Obtained HNMR of the a small volume of sample UCExp260-1A and UCExp260-2A in CDCl3. It appears like sample UCExp260-2A has a slight dusting at the bottom of the vial.
help on how to format text
Turn off "Getting Started"