Acetic Anhydride → 2-Bromo-n-valeramide

A stirred solution of 100 g. (0.55 mole) of 5-bromovaleramide, 62.4 g. (0.61 mole) of acetic anhydride, and 5.4 g. (0.055 mole) of concentrated sulfuric was heated on a steam bath under nitrogen for 1.5 hours (internal temperature 93°). The mixture was then cooled to room temperature diluted with 250 ml. of water. The resultant tan granular precipitate was collected by filtration and dissolved in 600 ml. of methylene chloride. The solution was washed with saturated sodium bicarbonate (100 ml.) and saturated brine (100 ml.), was dried (anhydrous magnesium sulfate), treated with Darco, and filtered. Hexane was added to effect crystallization which afforded 64.8 g. (53.0% yield) of N-acetyl-5-bromovaleramide melting at 88°-90° .

1. temperature(0.055 mole) of concentrated sulfuric was heated on a steam bath under nitrogen for 1.5 hours (internal temperature 93°)
2. additiondiluted with 250 ml
3. filtrationThe resultant tan granular precipitate was collected by filtration
4. dissolutiondissolved in 600 ml
5. washThe solution was washed with saturated sodium bicarbonate (100 ml.) and saturated brine (100 ml.)
6. dry with materialwas dried (anhydrous magnesium sulfate)
7. additiontreated with Darco
8. filtrationfiltered
9. additionHexane was added to effect crystallization which
10. customafforded 64.8 g

ORD record

ord-9360368742a147f6b3048ff996883cd0

Source dataset

uspto-grants-1976_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US03954741