Ammonia → Methyl 3-oxohexanoate

56 g (1 mol) of calcium oxide were placed in 650 ml of methylene chloride, and 116 g (1 mol) of methyl acetoacetate were added dropwise at 20° to 30° C. over 0.5 hour. Stirring was then continued for 1 hour at this temperature. 116 g (1.05 mol) of butyryl chloride were then metered in at a temperature of 30°-35° C. over one hour and stirring was then continued for 3 hours at this temperature. 54 g (1 mol) of ammonium chloride in 300 ml of water were then added to the viscous suspension at 30° C. and the resulting mixture was stirred for 30 minutes. The pH of the reaction mixture was adjusted to 9 with aqueous ammonia and stirring was continued for 3 hours at 30° C. After the reaction mixture had been acidified with concentrated hydrochloric acid (pH<1), it was washed with sodium bicarbonate solution and water. After separation of the water phase, the solvent was distilled off on an evaporator. This gave 141 g (GC purity 73%) of methyl butyrylacetate (yield 71%).

1. stirringstirring
2. waitwas then continued for 3 hours at this temperature
3. stirringthe resulting mixture was stirred for 30 minutes
4. stirringstirring
5. waitwas continued for 3 hours at 30° C
6. washwas washed with sodium bicarbonate solution and water
7. customAfter separation of the water phase
8. distillationthe solvent was distilled off on an evaporator

ORD record

ord-de338c702407492a976ca0d8b74beee3

Source dataset

uspto-grants-1993_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05194671