Objective

To synthesize eight Ugi products with benzaldehyde, propylamine and 1-pyrenebutyric acid with eight different isocyanides in THF.

Procedure

A homogeneous solution of benzaldehyde (5mmol, 508uL), propylamine (5mmol, 411uL) and 1-pyrenebutyric acid (5mmol, 1441.7mg) was made up in 5mL volumetric flask. The solution (500uL, 0.5mmol per component) was transferred in to eight labeld one dram vials. To each vial a unique isocyanide (0.5mmol) was added. The obtained solutions were vortexed for 10s each to ensure a homogeneous solution was obtained. The vials containing the reaction mixtures were left undisturbed overnight at room temperature.

Results

Pictures
IMG-UCExp224-1
IMG-UCExp224-2
IMG-UCExp224-3
IMG-UCExp224-4
Spreadsheet

Discussion

None of the solutions formed any crystalline product; therefore it is assumed that it is not very likely to prepare crystalline Ugi products of 1-pyrenebutyric acid in THF with benzaldehyde, propylamine and the isocyanides used at about 0.9M concentration per component.

Conclusion

No Ugi products precipitated out from THF solution of the starting materials used at a concentration of about 0.9M per component.

Log

2009-05-19
17:00 A one molar solution of benzaldhyde, propylamine and 1-pyrenebutyric acid was made-up in a 5mL volumetric flask by placing benzaldehyde (5mmol, 508uL), THF (~2mL initially), propylamine (5mmol, 411uL) and 1-pyrenebutyric acid (5mmol, 1441.7mg). The solution was made-up to the mark by adding required amount of THF....most of the acid dissolved in the solution immediately, however some of it still remained undissolved at the bottom, therefore sonication was applied.
17:30 Placed the volumetric flask in the sonciation with water bath at room temp (20C), obtained a picture (IMG-UCExp224-1) of the volumetric flask in the sonicator.
17:45 Removed the flask from the sonicator (no change in the temp in the water bath); all the acid appeared to have dissolved in the solution.
17:55 Obtained a picture (IMG-UCExp224-2) of the clear solution in the volumetric flask..this solution is labeled '224-O'
18:20 Labeled eight vials as 224-1, 224-2, 224-3, 224-4, 224-5, 224-6, 224-7 and 224-8.
18:25 Placed 500uL of the solution 224-O in to the above labeled eight vials
18:50 Added the following isocyanides to the corresponding vials. After the addition of the isocyanide to the vials they were vortexed for 10s and made sure a homogeneous solution was obtained.
Sample Number
Isocyanide added
Amt of
isocyanide added(0.5mmol)
224-1
t-butylisocyanide
56.5uL
224-2
n-butylisocyanide
52.3uL
224-3
n-pentylisocyanide
63uL
224-4
cyclohexylisocyanide
62.2uL
224-5
benzylisocyanide
61uL
224-6
TOSMIC
97.6mg
224-7
Morpholinoethyl isocyanide
69uL
224-8
2-chloro-6-methylphenyl isocyanide
75.8mg
19:20 Obtained a picture (IMG-UCExp224-3) of the vials containing eight solutions ..Not sure why but appears like most solution vials have accumulated some amount of solid at the bottom of the vials...wonder if the reaction rate is so fast that the Ugi products crystals are falling out of the solution or if 1-pyrenebutyric acid is...infact it would be weird if the acid is falling out, because a homogenenous solution of 224-O was definitely obtained after sonication..
2009-05-20
22:00 Obtained a picture of the solutions in the vials; hardly any changes noticeable in any of the vials (IMG-UCExp224-4)...vial 224-6 which had TOSMIC shows some ppt..believe it could be the isocyanide that might have crashed out. In almost all the vials there is some coating of a powdery mass at the bottom of the vials, which may be one of the starting materials crashing out.