Objective

To study the kinetics of a Ugi reaction of phenanthrene-9-carboxaldehyde, furfurylamine, phenylacetic acid and n-butylisocyanide in methanol at room temperature.

Procedure

A 0.1M solution (254-A) of furfurylamine (0.1mmol, 10mg), phenanthrene-9-carboxaldehyde (0.1mmol, 21mg) and phenylacetic acid (0.1mmol, 14mg) was made-up in methanol in a 1mL volumetric flask. The solution was left to reach equilibrium for 1h.
In a 1mL volumetric flask a 0.4M solution (254-B) of n-butylisocyanide (0.4mmol, 42uL) was made-up in methanol.
In to a clean NMR tube with a co-axial insert (with DMSO-d6, 125uL) 254-A (0.05mmol / component, 500uL) was transferred. A HNMR of the solution (254A) was obtained. Soon after transferred 254B (0.05mmol, 125uL) was transferred to the NMR tube and the reaction was followed to obtain the kinetics, until crystals started to appear in the solution. The reaction was carried out at 0.08M concentration per component.


Results

HNMRs
Spreadsheet UCExp254
Crystals developing in the NMR tube
UCExp254-1A-IMG-ix

Discussion

The solubility of the Ugi product UC176C in methanol had been determined to be 0.02M. If the reaction in the NMR tube goes to completion the expected concentration of the Ugi product would be 0.08M. Assuming there was a negligible effect of co-solutes on the solubility of the Ugi product, precipitation should not take too long based on previously performed synthesis of UC176C, as in Exp253, Exp251

Conclusion

Log

2009-12-06
18:20 Weighed out furfurylamine (10mg) in to a 1mL volumetric flask.
18:30 Weighed phenanthrene-9-carboxaldehyde (21mg) and phenylacetic (14mg)
18:45 Added the weighed out aldehyde and acid to the amine in the volumetric flask.
18:50 Transferred methanol in to flask and made the solution up to the 1mL mark. Vortexed the solution for a few seconds, was unable to dissolve completely.
18:51 Left the volumetric flask with the solution in the sonicator bath..
19:00 The solution had cleared-up completely, removed from the bath. This solution is named 254A
2009-12-07
06:55 Made-up a 0.4M solution of butylisocyanide (42uL) in methanol in a 1mL volumetric flask. This solution is named 254B
07:20 Transferred 500uL of 254A in to a NMR tube with a DMSO-d6 containing coaxial insert.
07:50 Obtained HNMR of 254A, UCExp254A.
08:02 Pipetted out 125uL (0.05mmol) of 254B in to the NMR tube t=0min, the solution in the NMR tube is now labeled UCExp254-1A
08:07 Obtained HNMR of UCExp254A - 05min
08:11 Obtained HNMR of UCExp254A - 09min
08:15 Obtained HNMR of UCExp254A - 13min
08:21 Obtained HNMR of UCExp254A - 19min
08:26 Obtained HNMR of UCExp254A - 24min
08:30 Obtained HNMR of UCExp254A - 28min
08:39 Obtained HNMR of UCExp254A - 37min
08:44 Obtained HNMR of UCExp254A - 42min
09:00 Obtained HNMR of UCExp254A - 58min
09:06 Obtained HNMR of UCExp254A - 1h04min (64min)
09:14 Obtained HNMR of UCExp254A - 1h12min (72min
09:20 Obtained HNMR of UCExp254A - 1h18min (78min)
09:27 Obtained HNMR of UCExp254A - 1h25min (85min)
09:32 Obtained HNMR of UCExp254A - 1h30min (90min)
09:41 Obtained HNMR of UCExp254A - 1h39min (99min)
09:50 Obtained HNMR of UCExp254A - 1h48min (108min)
10:00 Obtained HNMR of UCExp254A - 1h58min (118min)
10:10 Obtained HNMR of UCExp254A - 2h08min (128min)
10:22 Obtained HNMR of UCExp254A - 2h20min (140min)
11:42 Obtained HNMR of UCExp254A - 3h40min (220min)
11:57 Obtained HNMR of UCExp254A - 3h55min (235min)
12:16 Obtained HNMR of UCExp254A - 4h14min (254min)
12:20 Obtained HNMR of UCExp254A - 4h18min (258min)
12:29 Obtained HNMR of UCExp254A - 4h27min (267min)
14:00 Left the NMR tube in a sonicator and set it to sonicate for 5min.
14:00 Removed the tube from the sonicator, no crystals yet in the tube.
14:27 Observed a few tiny crystals developing in the tube.
14:40 Obtained pictures of the tube with crystals in it, UCExp254-1A-ix and others
15:16 Obtained HNMR of UCExp254A - 7h14min (434min)