Exp114-iii.JPG

Objective

To synthesize a Ugi adduct from furfuraldehyde, methylamine, benzylisocyanide and α,4-dimethylphenylacetic acid following the EXPLAN005 in methanol.

Procedure

To a 2.0M solution of methylamine in methanol (250ul, 0.5 mmol) was added methanol (250uL) furfuraldehyde (41.5uL, 0.5 mmol), α,4-Dimethylphenylacetic acid (82.1mg, 0.5 mmol) and benzylisocyanide (60.5uL, 0.5 mmol) in a 1.5 ml Eppendorf tube in that order, with 15 s mixing after each addition. The reaction mixture was left undisturbed overnight. The solution was then vortexed and centrifuged. The residue was washed successively with methanol (2 the protocol calls for 3 washes x 500uL), centrifuged and dried under vacuum.

Results

Characterization of 114A

brown solid, 7.2 mg
HNMR (however sparingly soluble in CDCl3)

Discussion

The small amount of brown precipitate obtained after methanol washes was sparingly soluble in CDCl3, which is uncharacteristic of the typical Ugi products we have obtained in the past. Either the Ugi product is too soluble in methanol and was washed away or the reaction did not proceed.

Conclusion

The Ugi product was not isolated.

Log

2007-07-24

15:10 Weighed Eppendorf tube (0.8271g) and labeled
15:14 Added methanol (250uL) to tube
15:15 Added methylamine (250uL) to tube and vortexed for 15 s
15:17 Added furfuraldehyde (41.5uL) to solution and vortexed for 15 s, observed orange solution
15:19 Added α,4-Dimethylphenylacetic acid (82.1mg) to solution and vortexed for 15 s
15:21 Added benzylisocyanide (60.5uL) to solution and vortexed for 15 s, observed brown color, all compounds dissolved
15:24 Placed under fume hood to sit undisturbed overnight
16:17 Observed solution with about half appearing as a brown solid in the Eppendorf tube

2007-07-25

11:00 Observed brown solid on the bottom of tube, a lighter brown solid formed above this, and the remaining purple colored liquid
11:20 Mixed tube on vortex for 15 seconds
11:30 Centrifuged at 14000 RPM for 60 seconds, then discarded supernatant
11:33 Added methanol (500uL), mechanically mixed on vortex for 15 seconds
11:35 Centrifuged at 14000 RPM for 60 seconds, then discarded supernatant
11:38 Added methanol (500uL), mechanically mixed on vortex for 15 seconds
11:40 Centrifuged at 14000 RPM for 60 seconds, then discarded supernatant
11:45 Put open tube under vacuum with 7mm pressure
14:45 Took Eppendorf tube with a solid out of the vacuum, weighed it (.8343g)
15:44 Took H NMR of brown solid partially dissolved in CDCl3 (800uL) [There was solid still hanging in the nmr tube]