Iodoethane → 1,3-Dibromo-2-ethylbenzene

HRID 389642Notes

Reaction equation

HRID 389642 reaction equation
[Br:1][C:2]1[CH:7]=[CH:6][CH:5]=[C:4]([Br:8])[CH:3]=1.[CH2:9](I)[CH3:10].[Li+].CC([N-]C(C)C)C.[NH4+].[Cl-]>C1COCC1>[Br:1][C:2]1[CH:7]=[CH:6][CH:5]=[C:4]([Br:8])[C:3]=1[CH2:9][CH3:10]

Participants

6

Reactant 4

HCID 6340IodoethaneHCID 79271,3-DibromobenzeneHCID 25517Ammonium ChlorideHCID 2724682Lithium diisopropylamide

Product 1

HCID 148478061,3-Dibromo-2-ethylbenzeneYield 123.1%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Conditions

Temperature
-78 °C

Procedure

A three necked round-bottom flask was purged with argon and then filled with dry THF (1.2 I), 1,3-dibromo benzene (121 g, 0.514 mol) and ethyl iodide (95.4 g, 0.611 mol). The mixture was cooled to −78° C. and LDA (64.2 g, 0.697 mol) (2 M in THF/n-heptane/ethylbenzene) was added slowly in a way that the temperature didn't rise above −65° C. After stirring for 2.75 h the reaction was poured onto 11 sat. aq NH4Cl solution and stirred vigorously for 20 min. Extraction with DCM (twice) yielded a colorless oil (167 g) which was used in the next step without further purification

Workup

  1. customA three necked round-bottom flask was purged with argon
  2. customrise above −65° C
  3. stirringstirred vigorously for 20 min
  4. extractionExtraction with DCM (twice)

Sources & evidence

ORD record
ord-74ead2cd14d14cb8b848d4c671ae4ab7
Source dataset
uspto-grants-2013_02
Patent number
US08378092B2

Reaction notes

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