Methyl acetoacetate → Methyl 3-oxooctadecanoate

Four liters of a suspension of 440 g (11 mol) of 60% sodium hydride in dried tetrahydrofuran was cooled to 0° C. Thereto was added dropwise 1.8 L of a tetrahydrofuran solution of 1.161 kg (10 mol) of methyl acetoacetate. After this mixture was stirred at room temperature for 1 hour, 3.023 kg (11 mol) of hexadecanoyl chloride was added dropwise at 0 to 5° C. and the resultant mixture was stirred at room temperature overnight. Thereafter, the tetrahydrofuran was distilled off, and the residue was poured into ice water and extracted with 8 L of ethyl acetate. The ethyl acetate was distilled off, and the residue was poured into a mixture of 400 g of a 28% methanol solution of sodium methoxide and 1.2 L of methanol. The resultant mixture was stirred with heating at 60 to 65° C. for 6 hours. The reaction mixture was cooled with ice, and the pH thereof was then adjusted to 5 with 10% sulfuric acid. This reaction mixture was extracted with ethyl acetate. The ethyl acetate layer was washed with 5% aqueous sodium carbonate solution and saturated aqueous common salt solution. Thereafter, the ethyl acetate was distilled off and the concentrate was recrystallized from methanol to obtain 1.72 kg (5.5 mol) of methyl 3-oxooctadecanoate. Yield, 55%.

1. distillationThereafter, the tetrahydrofuran was distilled off
2. additionthe residue was poured into ice water
3. extractionextracted with 8 L of ethyl acetate
4. distillationThe ethyl acetate was distilled off
5. additionthe residue was poured into a mixture of 400 g of a 28% methanol solution of sodium methoxide and 1.2 L of methanol
6. stirringThe resultant mixture was stirred
7. temperaturewith heating at 60 to 65° C. for 6 hours
8. temperatureThe reaction mixture was cooled with ice
9. extractionThis reaction mixture was extracted with ethyl acetate
10. washThe ethyl acetate layer was washed with 5% aqueous sodium carbonate solution and saturated aqueous common salt solution
11. distillationThereafter, the ethyl acetate was distilled off
12. customthe concentrate was recrystallized from methanol

ORD record

ord-f5aa57b92b374caca01d02cdc1fc8fd8

Source dataset

uspto-grants-1999_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05998668