Ammonia → Ethyl imino(2-bromopyridin-5-yl)acetate

Participants

Reaction Steps

Under nitrogen, 299 mL (4.20 mol) of acetyl chloride was added dropwise to a solution of 299 mL (5.11 mol) of absolute ethanol and 400 mL of chloroform at 0° C. A solution of 72.0 g (370 mmol) of 2-bromo-5-cyanomethylpyridine from step 5 in 1100 mL of chloroform was added dropwise with stirring. Stirring was continued at 0° C. for 4 h and the reaction was allowed to come to ambient temperature overnight. The reaction was diluted with 2500 mL of anhydrous ether and stirring was continued for an additional 2 h. The precipitated imidate hydrochloride salt was collected by filtration in a glove bag under nitrogen and washed with anhydrous ether. Under nitrogen, a mechanically stirred suspension of this material in 3500 mL of anhydrous ether at -78° C. was treated with 36 g (2.1 mol) of anhydrous ammonia. The reaction was allowed to slowly warm to ambient temperature overnight and the ammonium chloride removed by filtration. The filtrate was concentrated in vacuo giving 78.7 g (89%) of crude ethyl imino(2-bromopyridin-5-yl)acetate as a brown oil: NMR (CDCl3)δ1.29 (t, J=7 Hz, 3 H), 3.51 (s, 2 H), 4.13 (q, J=7 Hz, 2 H), 7.43 (dd, J=8 and 2 Hz, 1 H), 7.48 (d, J=8 Hz, 1 H), 8.26 (d, J=2 Hz, 1 H); MS (FAB) m/e (rel intensity) 245 (100), 243 (90), 217 (35), 215 (38), 200 (5), 198 (5).

Provenance & Evidence