Exp102-11-2.JPG

Objective

To accomplish a Friedel-Crafts tert-butylation of N-(2-furylmethyl)acetamide with tert-butanol. [Exp105, Iovel 1998]

Procedure

N-(2-furylmethyl)acetamide (562.8mg, 2.88mmol, 103A) was added to t-butanol (15mL) with concentrated sulfuric acid (1 mL). The reaction mixture was stirred overnight at room temperature. After 20h of stirring at room temperature it was refluxed for 5 hours.

Results

N-(2-furylmethyl)acetamide
H NMR (Prepared in Exp 103)
102A (40uL in CDCl3)
H NMR (12min)
H NMR (48min)
H NMR (17h 13min)
H NMR (20h 55min including 5h reflux)
H NMR (2days)

Discussion

The reaction mixture after two days (including 5h reflux) does not seem to contain a desired quantity of the tert-butylated product. This maybe because of acidophobic character of furan (Iovel 1998) as result of which the furan ring may have opened up.

Conclusion

The reaction has been aborted.

Log

2007-06-05

16:30 Distilled 100ml of tert-butyl alcohol at 82C (data not recorded)
19:47 Added N-(2-furylmethyl)acetamide, freshly distilled tert-butanol (15ml) and conc. sulfuric acid in a round bottom flask. The reaction mixture was constantly stirred on a stir plate.This is 102A
19:57 Removed 40uL of 102A, dissolved it in CDCl3 (800uL) and obtained H NMR (12min)
20:35 Obtained H NMR by dissolving 40uL of 102A in CDCl3 (800uL). (48min)

2007-06-06

13:00 Obtained H NMR by dissolving 40uL of 102A in CDCl3 (800uL) (17h 13min)
15:50 Started refluxing the reaction mixture. (note time turned heat on and setting on mantle then note time when refluxed observed to start - at least one drop per 2-3 sec)
16:42 Obtained H NMR by dissolving 150uL of 102A in CDCl3 (800uL) (20h 55min)
20:00 Turned the heat off.

2007-06-07

11:12 Obtained H NMR by dissolving 150uL of 102A in CDCl3 (800uL) (2days)



References
  1. Exp105
  2. I. Iovel'. et.al Chemistry of Heterocyclic Compounds; Vol.34, Iss.1.pp 1-12

Tags

N-(2-furylmethyl)acetamide: InChI=1/C7H9NO2/c1-6(9)8-5-7-3-2-4-10-7/h2-4H,5H2,1H3,(H,8,9)