Acetic Anhydride → 6-Acetoxyhexylacrylamide

Participants

Reaction Steps

6-Hydroxyhexylacrylamide (4.00 gm, 23.4 mmole), acetic anhydride (4.41 mL, 46.8 mmole) and dimethylamino pyridine (23.3 mg, 2.3 mmole) were dissolved in 15 mL of pyridine and were allowed to react at room temperature for 4 hours. After evaporation of the solvents the residue was dissolved in 100 mL of ethyl acetate and was washed with N HCl and brine. After drying over Na2SO4 the organic solution was filtered and the solvent was removed in vacuo to yield a yellow syrup. Crystallisation was induced by adding and evaporating benzene followed by hexane. Crude yield: 4.84 gm, mp 38°-45° C. 3.5 gm of this crude product was dissolved in 20 mL of EtOAc, decolorised with charcoal and was dropped into 200 mL of hexane. On stirring the material crystallised. After sitting at 4° C. overnight the product was collected. Yield 2.50 gm (71% recrystallised) mp 43°-43.5° C. TLC Rf 0.47 (CHCl3 :MeOH 9:1). NRM:δ(CDCl3) 6.67 (br s, 1 H, NH), 5.5-6.4 (M, 3 H, CH2 =CH--), 4.03 (tr, J=6 Hz, 2 H, CH2O) 3.30 (br q, 3 H, CH2N), 2.02 (s,3 H, COCH3), 1.4 (m, 8 H, (CH2)4). Analysis: C11H19NO3 requires C, 61.95%; H, 898%; N, 6.56%. Found: C, 62.09%; H, 9.09%; N, 6.51%.

Provenance & Evidence