Pyridine → 5-bromo-1H-indene

HRID 1017150Notes

Reaction equation

HRID 1017150 reaction equation
[Br:1][C:2]1[CH:3]=[C:4]2[C:8](=[CH:9][CH:10]=1)[CH:7](O)[CH2:6][CH2:5]2.N1C=CC=CC=1.C1(C)C=CC(S(Cl)(=O)=O)=CC=1>C1(C)C=CC=CC=1>[Br:1][C:2]1[CH:3]=[C:4]2[C:8](=[CH:9][CH:10]=1)[CH2:7][CH:6]=[CH:5]2

Participants

5

Reactant 3

HCID 1049PyridineHCID 73974-Toluenesulfonyl chlorideHCID 134862995-bromo-2,3-dihydro-1H-inden-1-ol

Product 1

HCID 27475715-bromo-1H-indeneYield 46.4%

Reagents, catalysts & solvents 1

HCID 1140TolueneSolvent

Procedure

A 1 L three-neck round bottom flask equipped with a condenser, magnetic stir bar, nitrogen inlet, and a thermometer was charged with 5-bromo-1-indanol (56.5 g, 0.265 mol), toluene (300 mL), pyridine (250 mL, 3.1 mol), and p-toluenesulfonyl chloride (55.3 g, 0.29 mol). The mixture was stirred and heated to reflux while dehydration progress was followed by GC. After 7 hours at reflux the dark colored reaction mixture was cooled, quenched by pouring over ice-water (700 mL) containing HCl (12M, 200 mL) and extracted several times with diethyl ether (3×250 mL). The combined diethyl ether extracts were washed repeatedly with water, 5% sodium bicarbonate (aqueous), and water then dried over anhydrous magnesium sulfate. Evaporation of diethyl ether followed by vacuum distillation (80° C./0.5 mm Hg) gave 5-bromoindene (24.0 g, 99+% purity by GC) as a colorless oil. 1HNMR (CD2Cl2, 500 MHz) δ7.59 (br s, 1H); 7.38 (dd, JAB=1.5, 8 Hz, 1H), 7.26 (d, JAB=8 Hz, 1H); 6.84 (m, 1H); 6.56 (m, 1H); 3.39 (s, 2H).

Workup

  1. customA 1 L three-neck round bottom flask equipped with a condenser, magnetic stir bar, nitrogen inlet
  2. temperatureheated
  3. temperatureto reflux while dehydration progress
  4. temperatureAfter 7 hours at reflux the dark colored reaction mixture
  5. temperaturewas cooled
  6. customquenched
  7. additionby pouring over ice-water (700 mL)
  8. additioncontaining HCl (12M, 200 mL)
  9. extractionextracted several times with diethyl ether (3×250 mL)
  10. washThe combined diethyl ether extracts were washed repeatedly with water, 5% sodium bicarbonate (aqueous), and water
  11. dry with materialthen dried over anhydrous magnesium sulfate
  12. customEvaporation of diethyl ether
  13. distillationfollowed by vacuum distillation (80° C./0.5 mm Hg)

Sources & evidence

ORD record
ord-5e0ff51ef2644cfabcd71a2bf14d8dcf
Source dataset
uspto-grants-2002_11
Patent number
US06479424B1

Reaction notes

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