Dimethyl Disulfide → 1-Bromo-4-chloro-3-methylthio-2-fluorobenzene

HRID 495020Notes

Reaction equation

HRID 495020 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

  1. additionAfter addition
  2. temperaturecooled to −50° C
  3. temperaturethe mixture was warmed to ambient temperature
  4. customThe reaction was quenched with water (200 mL)
  5. extractionextracted with ethyl acetate (2×150 mL)
  6. customthe combined organic phases dried
  7. concentrationconcentrated
  8. 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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