Reaction equation
[F:1][C:2]1[CH:7]=[C:6]([F:8])[CH:5]=[CH:4][C:3]=1[Mg]Br.FC1C=C(F)C=CC=1Br.[Mg].[C:21]([O:24][CH2:25][C:26]([CH2:28][O:29][C:30](=[O:32])[CH3:31])=[O:27])(=[O:23])[CH3:22].Cl>C1COCC1>[C:30]([O:29][CH2:28][C:26]([C:3]1[CH:4]=[CH:5][C:6]([F:8])=[CH:7][C:2]=1[F:1])([OH:27])[CH2:25][O:24][C:21](=[O:23])[CH3:22])(=[O:32])[CH3:31]Participants
Conditions
- Temperature
- -30 °C
Procedure
Under an atmosphere of argon, 850 ml of THF solution of 2,4-difluorophenylmagnesium bromide prepared from 202.6 g (1.05 mol) of 2,4-difluorobromobenzene and 26.7 g (1.1 mol) of magnesium turnings was added dropwise at -30° C. to 1.7 l of THF solution of 174 g (1.00 mol) of 1,3-diacetoxyacetone which was previously cooled to -30° C. After the resulting liquid was stirred at -60° C. for 2 hours, a temperature thereof was gradually raised to room temperature. Then, to the reaction mixture was added 1 l of 1.2N aqueous solution of hydrochloric acid at 5° C. or below, and an aqueous layer was extracted twice with 1 l of ethyl acetate. The organic layer was washed with saturated aqueous solution of sodium chloride, dried and concentrated under reduced pressure to give 302 g of crude oil. The obtained oil was purified by means of column chromatography on silica gel (hexane:ethyl acetate=1:1) to give 125 g of the desired compound. The compound was recrystallized from toluene/hexane.
Workup
- temperaturea temperature thereof was gradually raised to room temperature
- extractionan aqueous layer was extracted twice with 1 l of ethyl acetate
- washThe organic layer was washed with saturated aqueous solution of sodium chloride
- customdried
- concentrationconcentrated under reduced pressure
- customto give 302 g of crude oil
- customThe obtained oil was purified by means of column chromatography on silica gel (hexane:ethyl acetate=1:1)
Sources & evidence
- ORD record
- ord-482eb7ee2b7d4fa4af568fab801c7ce8
- Source dataset
- uspto-grants-1998_11
- Patent number
- US05840553
Linked notes
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