Iodine → 7-[2-[4-(Methylthio)phenyl]ethoxy]-2-heptanone

HRID 568881Notes

Reaction equation

HRID 568881 reaction equation
Br[CH2:2][CH2:3][CH2:4][CH2:5][CH2:6][O:7][CH2:8][CH2:9][C:10]1[CH:15]=[CH:14][C:13]([S:16][CH3:17])=[CH:12][CH:11]=1.[Mg].II.[C:21](OC(=O)C)(=[O:23])[CH3:22]>[Cl-].[NH4+]>[CH3:17][S:16][C:13]1[CH:14]=[CH:15][C:10]([CH2:9][CH2:8][O:7][CH2:6][CH2:5][CH2:4][CH2:3][CH2:2][C:21](=[O:23])[CH3:22])=[CH:11][CH:12]=1

Participants

6

Reactant 4

HCID 807IodineHCID 7918Acetic AnhydrideHCID 5462224MagnesiumHCID 200713861-[2-[(5-Bromopentyl)oxy]ethyl]-4-(methylthio)benzene

Product 1

HCID 200714087-[2-[4-(Methylthio)phenyl]ethoxy]-2-heptanoneYield 49.1%

Reagents, catalysts & solvents 1

HCID 25517Ammonium ChlorideSolvent

Procedure

The product of stage (i) (5.00 g) in ER (7.0 ml) was added dropwise to magnesium turnings (0.384 g) with one crystal of iodine at room temperature under nitrogen with stirring. The stirred mixture was heated to reflux for 3 h under nitrogen and the solution of Grignard reagent was added slowly to a stirred solution of acetic anhydride (2.86 g) in ER (70 ml) over a period of 1 h maintaining the temperature between -60° and -70°. After a further 2 h at -60° to -70°, the reaction mixture was allowed to warm to -10° and treated with a saturated aqueous ammonium chloride solution (20 ml). The ER layer was separated and the aqueous phase was extracted with ER (3×40 ml). The combined extracts were washed with 2N sodium hydroxide (30 ml) and brine (30 ml). The washings were extracted with ER (3×40 ml) and these extracts, combined with the previous extracts were dried and evaporated. The residual oil (3.73 g) was purified by FCC eluting with ER-H (1:14→1:7) followed by ER-CX (1:7 to give the title compound (2.17 g).

Workup

  1. temperatureThe stirred mixture was heated
  2. temperatureto reflux for 3 h under nitrogen
  3. temperaturemaintaining the temperature between -60° and -70°
  4. temperatureto warm to -10°
  5. customThe ER layer was separated
  6. extractionthe aqueous phase was extracted with ER (3×40 ml)
  7. washThe combined extracts were washed with 2N sodium hydroxide (30 ml) and brine (30 ml)
  8. extractionThe washings were extracted with ER (3×40 ml)
  9. customwere dried
  10. customevaporated
  11. customThe residual oil (3.73 g) was purified by FCC
  12. washeluting with ER-H (1:14→1:7)

Sources & evidence

ORD record
ord-4c5f5dec63774e0084ded0c0c0005298
Source dataset
uspto-grants-1988_03
Patent number
US04730008

Reaction notes

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