Triethylsilane → 6-(2-Bromo-5-iodobenzyl)-2,3-dihydrobenzo[b][1,4]dioxine

HRID 1022464

Reaction equation

HRID 1022464 reaction equation
[Br:1][C:2]1[CH:7]=[CH:6][C:5]([I:8])=[CH:4][C:3]=1[C:9]([C:11]1[CH:20]=[CH:19][C:14]2[O:15][CH2:16][CH2:17][O:18][C:13]=2[CH:12]=1)=O.C([SiH](CC)CC)C.OS(C(F)(F)F)(=O)=O>FC(F)(F)C(O)=O.OS(C(F)(F)F)(=O)=O>[Br:1][C:2]1[CH:7]=[CH:6][C:5]([I:8])=[CH:4][C:3]=1[CH2:9][C:11]1[CH:20]=[CH:19][C:14]2[O:15][CH2:16][CH2:17][O:18][C:13]=2[CH:12]=1

Participants

6

Reactant 3

HCID 12052TriethylsilaneHCID 62406Trifluoromethanesulfonic acidHCID 58340798Methanone, (2-bromo-5-iodophenyl)(2,3-dihydro-1,4-benzodioxin-6-yl)-

Product 1

HCID 583408306-(2-Bromo-5-iodobenzyl)-2,3-dihydrobenzo[b][1,4]dioxineYield 84.3%

Reagents, catalysts & solvents 2

HCID 62406Trifluoromethanesulfonic acidCatalystHCID 6422Trifluoroacetic acidSolvent

Procedure

(Note: This reaction was done in 5 lit. R. B. flask). To a stirred solution of (2-bromo-5-iodo-phenyl)-(2,3-dihydro-benzo[1,4]dioxin-6-yl)-methanone (180 g, 404.49 mmol) in trifluoroacetic acid (600 ml) was added triethylsilane (386.5 ml, 2426.9 mmol) followed by triflic acid (2.3 ml) at room temperature (note: after addition of 1 drop of triflic acid exotherm was observed so addition was done very slowly in such a way that reaction mixture refluxed gently). After stirring for 25 min at room temperature, volatiles were evaporated under reduced pressure. The resulting residue was taken in ethyl acetate (1500 ml) and washed with saturated aqueous sodium bicarbonate solution (1000 ml×2), water (1000 ml), brine (1000 ml), dried over sodium sulfate, and concentrated. The resulting residue was triturated with hexane. The residue was recrystallized from ethanol to give 147 g of 6-(2-bromo-5-iodo-benzyl)-2,3-dihydro-benzo[1,4]dioxine.

Workup

  1. additionwas observed so addition
  2. customthat reaction mixture
  3. temperaturerefluxed gently)
  4. customvolatiles were evaporated under reduced pressure
  5. washwashed with saturated aqueous sodium bicarbonate solution (1000 ml×2), water (1000 ml), brine (1000 ml)
  6. dry with materialdried over sodium sulfate
  7. concentrationconcentrated
  8. customThe resulting residue was triturated with hexane
  9. customThe residue was recrystallized from ethanol

Sources & evidence

ORD record
ord-88c1275bcfb444548127d9b446d8a601
Source dataset
uspto-grants-2014_05
Patent number
US08722633B2

Linked notes

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