Bromine → 7-Bromo-5-chloro-2,3-dihydrobenzofuran

HRID 257516

Reaction equation

HRID 257516 reaction equation
[Cl:1][C:2]1[CH:3]=[CH:4][C:5]2[O:9][CH2:8][CH2:7][C:6]=2[CH:10]=1.[Br:11]Br.S([O-])([O-])(=O)=S.[Na+].[Na+]>C(O)(=O)C>[Cl:1][C:2]1[CH:3]=[C:4]([Br:11])[C:5]2[O:9][CH2:8][CH2:7][C:6]=2[CH:10]=1

Participants

5

Reactant 3

HCID 24408BromineHCID 24477Sodium ThiosulfateHCID 5929645-Chloro-2,3-dihydro-1-benzofuran

Product 1

HCID 197834187-Bromo-5-chloro-2,3-dihydrobenzofuranYield 92%

Reagents, catalysts & solvents 1

HCID 176Acetic AcidSolvent2×

Procedure

To a stirred solution of (33) (1.84 g, 11.93 mmol) in acetic acid (10 ml) at 0° C., was slowly added a solution of bromine (1.24 ml, 24 mmol) in acetic acid (5 ml). The reaction mixture was stirred at room temperature for 4.5 h. A 10% sodium thiosulphate solution (70 ml) was added and the mixture stirred for 10 min. The bulk of the solvent was evaporated in vacuo. The resulting oil was dissolved in ether (50 ml), washed with water (20 ml), saturated NaHCO2 (2×15 ml), brine (1×15 ml), dried Na2SO4 and evaporated in vacuo to give 2.55 g (92%) of (34) as a oil.

Workup

  1. stirringthe mixture stirred for 10 min
  2. customThe bulk of the solvent was evaporated in vacuo
  3. dissolutionThe resulting oil was dissolved in ether (50 ml)
  4. washwashed with water (20 ml), saturated NaHCO2 (2×15 ml), brine (1×15 ml), dried Na2SO4
  5. customevaporated in vacuo

Sources & evidence

ORD record
ord-f2c2ef8aac97430eba3688d429ad02ec
Source dataset
uspto-grants-1993_11
Patent number
US05262430

Linked notes

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