Water → Methyl 3-oxovalerate

116 g of acetoacetic acid methyl ester and 75 g of pyrrolidine were boiled in 350 ml of toluene on a water separator until the theoretical quantity of water was separated. The solution was added drop by drop at -40° C. to a suspension of 47 g of sodium amide in 800 ml of liquid ammonia. The ammonia was removed by allowing the temperature of the reaction solution to rise to -20° C., and then, at such temperature, a solution of 114 g of methyl bromide in 500 ml of toluene was added drop by drop. The reaction solution was filtered and the toluene was removed using a rotary evaporator. The residue, after the addition of 700 ml of methylene chloride and 102 g of concentrated hydrochloric acid thereto, was hydrolyzed for 1 hour at ambient temperature. The two phases were separated, the organic phase was dried and the solvent was removed. 120 g of 3-oxopentanoic acid methyl ester (92 percent) was obtained.

1. customwas separated
2. additionThe solution was added drop by drop at -40° C.
3. additionto a suspension of 47 g of sodium amide in 800 ml of liquid ammonia
4. customThe ammonia was removed
5. customto rise to -20° C.
6. additionat such temperature, a solution of 114 g of methyl bromide in 500 ml of toluene was added drop by drop
7. filtrationThe reaction solution was filtered
8. customthe toluene was removed
9. customa rotary evaporator
10. additionThe residue, after the addition of 700 ml of methylene chloride and 102 g of concentrated hydrochloric acid
11. customThe two phases were separated
12. customthe organic phase was dried
13. customthe solvent was removed

ORD record

ord-deafcfe8817c4f54b75e642ded22dc42

Source dataset

uspto-grants-1985_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04545934