Benzene → 1210410-44-8

HRID 242446Notes

Reaction equation

HRID 242446 reaction equation
P(Br)(Br)[Br:2].[CH:5]1[CH:10]=[CH:9][CH:8]=CC=1.[C:11]([OH:15])([CH3:14])([CH3:13])[CH3:12].O.C[O:18][C:19](C)(C)C>>[Br:2][CH2:5][CH2:10][CH:9]([CH3:8])[C:19]([O:15][C:11]([CH3:14])([CH3:13])[CH3:12])=[O:18]

Participants

6

Reactant 5

HCID 241Benzene2×HCID 962Water2×HCID 6386tert-Butanol2×HCID 15413tert-Butyl methyl etherHCID 24614Phosphorus tribromide

Product 1

HCID 461789061210410-44-8Yield 28%

Conditions

Temperature
155 °C

Procedure

A mixture of α-methylbutyro-γ-lactone (86.5 g, 0.864 mol) and phosphorus tribromide (PBr3) (86 mL, 0.912 mol) was stirred at 150 to 160° C. for 3 hours under argon. The mixture was cooled to ambient temperature and anhydrous benzene (400 mL) was added. The resulting mixture was heated to reflux for 5 minutes and cooled to ambient temperature. The supernatant of the mixture was carefully transferred to a dry addition funnel with the aid of additional anhydrous benzene (40 mL). The solution in the addition funnel was added quickly to tert-butanol (t-BuOH) (320 g, 4.32 mol) with rapid stirring, while maintaining the internal temperature at 15 to 30° C. by means of a room temperature water bath. After complete addition of the solution to t-BuOH, the resulting mixture was stirred for 30 minutes at ambient temperature, and was then poured into a mixture of water, tert-butyl methyl ether (TBME) and ice. The organic layer was separated, washed with ice cold water, and then washed multiple times with saturated aqueous sodium bicarbonate until the pH of the aqueous layer was 8 to 9. The organic layer was then washed with brine, dried over sodium sulfate, and concentrated to dryness. The residue was applied to a silica gel column and eluted with ethyl acetate (0 to 5%) in hexane. Appropriate fractions were combined and concentrated to afford 1i as a clear oil (58 g, 28% yield). 1H NMR (CDCl3, δ): 1.17 (d), 1.48 (s), 1.90 (m), 2.23 (m), 2.59 (m), and 3.44 (m) ppm; 13C NMR (CDCl3, δ): 17.0, 28.2, 31.2, 36.5, 39.1, 80.6, and 175.1 ppm; MS (TOF) ESI+: [M+Na]+, 259.01, 261.02 Da.

Workup

  1. temperatureThe mixture was cooled to ambient temperature
  2. temperatureThe resulting mixture was heated
  3. temperatureto reflux for 5 minutes
  4. temperaturecooled to ambient temperature
  5. stirringthe resulting mixture was stirred for 30 minutes at ambient temperature
  6. customThe organic layer was separated
  7. washwashed with ice cold water
  8. washwashed multiple times with saturated aqueous sodium bicarbonate until the pH of the aqueous layer
  9. washThe organic layer was then washed with brine
  10. dry with materialdried over sodium sulfate
  11. concentrationconcentrated to dryness
  12. washeluted with ethyl acetate (0 to 5%) in hexane
  13. concentrationconcentrated

Sources & evidence

ORD record
ord-f70b3a84f45b46eb8b95712e8e773a66
Source dataset
uspto-grants-2014_02
Patent number
US08653131B2

Reaction notes

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