Ethyl 2-methylacetoacetate → Ethyl 2-methyl-3-oxohept-6-enoate

Ethyl 2-methyl-3-oxobutanoate (10 mL, 70.7 mmol) was added dropwise to an anhydrous tetrahydrofuran suspension of sodium hydride (2.83 g, 74.2 mmol) with stirring under ice cooling. The mixture was stirred for 15 minutes in this bath. Then, n-butyllithium (1.59 M hexane solution, 45.3 mL, 72.1 mmol) was added dropwise thereto, and the mixture was further stirred for 30 minutes. Then, allyl bromide (6.73 mL, 77.7 mmol) was added dropwise thereto. After removal of the ice bath, the mixture was stirred for 2 hours, and the reaction was then terminated by pouring dilute hydrochloric acid to the reaction solution. The reaction solution was subjected to extraction with ethyl acetate. The organic layer was washed with water, saturated aqueous sodium bicarbonate, and saturated saline and dried over anhydrous magnesium sulfate, and the solvent was then distilled off under reduced pressure. The obtained residue was purified by silica gel column chromatography to obtain the compound of interest as a pale yellow oil (7.67 g).

1. stirringThe mixture was stirred for 15 minutes in this bath
2. stirringthe mixture was further stirred for 30 minutes
3. customAfter removal of the ice bath
4. stirringthe mixture was stirred for 2 hours
5. customthe reaction was then terminated
6. additionby pouring dilute hydrochloric acid to the reaction solution
7. extractionThe reaction solution was subjected to extraction with ethyl acetate
8. washThe organic layer was washed with water, saturated aqueous sodium bicarbonate, and saturated saline
9. dry with materialdried over anhydrous magnesium sulfate
10. distillationthe solvent was then distilled off under reduced pressure
11. customThe obtained residue was purified by silica gel column chromatography

ORD record

ord-395dad0db0ff437280a208c3408a9422

Source dataset

uspto-grants-2011_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07947738B2