Réaction #57365

Équation de réaction

NaHMDS

cyclohexanone

acetic acid

methyl 2-[(4-fluorophenyl)methylene]-4-methyl-3-oxo-pentanoic acid

→

methyl 4-fluoro-α-(1-oxo-2-methylpropyl)-β-(2-oxocyclohexyl)benzenepropanoate

Solvants

THF

THF

THF

THF

water

THF

Conditions de réaction

Traitement

1. 1
   workup.ADDITIONAfter the addition
2. 2
   Températureto warm to room temperature
3. 3
   Températurewas cooled to −78° C. again
4. 4
   workup.STIRRINGThe reaction mixture was stirred at −78° C. for 3 h
5. 5
   TempératureAfter warming to room temperature the reaction
6. 6
   Extractionextracted with ethyl acetate (3×100 mL)
7. 7
   Lavagewashed with saturated aqueous sodium chloride solution (100 mL)
8. 8
   Séchagedried over magnesium sulfate
9. 9
   Filtrationfiltered
10. 10
    Concentrationconcentrated in vacuum

Mode opératoire

A NaHMDS solution in THF (112 mL, 1.0 M) was diluted with 50 mL of dry THF and cooled to −78° C. A solution of cyclohexanone (10.6 mL, 102 mmol) in 50 mL of dry THF was added dropwise over 10 min. After the addition, the mixture was allowed to warm to room temperature and stirred at 0° C. for 15 min before it was cooled to −78° C. again. A pre-cooled solution of methyl 2-[(4-fluorophenyl)methylene]-4-methyl-3-oxo-pentanoic acid (30.7 g, 123 mmol) in 30 mL of dry THF at −78° C. was added quickly via a cannula. The reaction mixture was stirred at −78° C. for 3 h and quenched with acetic acid (30 mL, 524 mmol) in 30 mL of THF. After warming to room temperature the reaction was diluted with 50 mL of water and extracted with ethyl acetate (3×100 mL). The organic fractions were combined, washed with saturated aqueous sodium chloride solution (100 mL), dried over magnesium sulfate, filtered and concentrated in vacuum to provide methyl 4-fluoro-α-(1-oxo-2-methylpropyl)-β-(2-oxocyclohexyl)benzenepropanoate a pale yellow oil: LCMS (method 5) tR=2.1 min; (ESI, pos. ion spectrum) m/z 349 (M+H).

Source