Dimethyl Disulfide → 1-Bromo-4-chloro-3-methylthio-2-fluorobenzene
Reaction equation
[Br:1][C:2]1[CH:7]=[CH:6][C:5]([Cl:8])=[CH:4][C:3]=1[F:9].[Li+].CC([N-]C(C)C)C.[CH3:18][S:19]SC>C1COCC1>[Br:1][C:2]1[CH:7]=[CH:6][C:5]([Cl:8])=[C:4]([S:19][CH3:18])[C:3]=1[F:9]Participants
5
Conditions
- Temperature
- -20 °C
Procedure
A solution of 1-bromo-4-chloro-2-fluorobenzene (20.4 g, 0.100 mol) in THF (50 mL) was slowly added to LDA (0.125 mol) in THF (600 mL) at −50° C. After addition, the solution was warmed to −20° C. and then cooled to −50° C. A solution of dimethyldisulfide (18.8 g, 0.20 mol) in THF (50 mL) was then slowly added and the mixture was warmed to ambient temperature. The reaction was quenched with water (200 mL), extracted with ethyl acetate (2×150 mL), and the combined organic phases dried and concentrated. The residual red oil was purified by chromatography (5% ethyl acetate in hexanes) to give 1-bromo-4-chloro-3-methylthio-2-fluorobenzene (23.9 g, 0.094 mol): 1H NMR (CDCl3): δ 7.40 (m, 1H), 7.15 (dd, 1H), 2.50 (s, 3H).
Workup
- additionAfter addition
- temperaturecooled to −50° C
- temperaturethe mixture was warmed to ambient temperature
- customThe reaction was quenched with water (200 mL)
- extractionextracted with ethyl acetate (2×150 mL)
- customthe combined organic phases dried
- concentrationconcentrated
- customThe residual red oil was purified by chromatography (5% ethyl acetate in hexanes)
Sources & evidence
- ORD record
- ord-2f37ce768c56439b818cbd84a60a39f1
- Source dataset
- uspto-grants-2009_05
- Patent number
- US07538214B2
Reaction notes
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