Phenethyl bromide → HCID 66702902, compound

HRID 424451Notes

Reaction equation

HRID 424451 reaction equation
[C:1]([C:3]1[S:4][C:5]2[CH:11]=[C:10]([OH:12])[CH:9]=[CH:8][C:6]=2[N:7]=1)#[N:2].C(=O)([O-])[O-].[K+].[K+].Br[CH2:20][CH2:21][C:22]1[CH:27]=[CH:26][CH:25]=[CH:24][CH:23]=1>CC(C)=O>[C:22]1([CH2:21][CH2:20][O:12][C:10]2[CH:9]=[CH:8][C:6]3[N:7]=[C:3]([C:1]#[N:2])[S:4][C:5]=3[CH:11]=2)[CH:27]=[CH:26][CH:25]=[CH:24][CH:23]=1

Participants

5

Reactant 3

HCID 7666Phenethyl bromide2×HCID 11430Potassium Carbonate2×HCID 98819122-Cyano-6-hydroxybenzothiazole

Product 1

HCID 66702902HCID 66702902, compoundYield 50.2%

Reagents, catalysts & solvents 1

HCID 180AcetoneSolvent

Procedure

A suspension of 2-cyano-6-hydroxybenzothiazole (1.00 g, 5.68 mmol) in acetone (5 mL) was prepared in a 100-mL 2-necked round-bottomed flask fitted with a reflux condenser. Anhydrous potassium carbonate (1.18 g, 8.52 mmol) was added to the reaction mixture and the suspension turned to a yellow solution. Then (2-bromoethyl)benzene (1.37 g, 0.88 mL, 7.38 mmol) was added and the reaction mixture was heated at reflux for using a heated stir plate and oil bath. Progress of the reaction was monitored by HPLC analysis of reaction aliquots. After 15 h of reflux the reaction was about 40% complete. Additional (2-bromoethyl)benzene (0.5 equivalents, 2.84 mmol) and potassium carbonate (0.5 equivalents, 2.84 mmol) were added periodically during the course of two days until the starting material was consumed. The reaction mixture was allowed to cool to ambient temperature and then filtered to remove inorganic salts. The filtrate was concentrated by rotoevaporation to provide 2.2 g of a crude oil. The crude product was purified by flash chromatography on silica gel using an initial mobile phase consisting of a mixture of 9:1 heptane-ethyl acetate. The mobile phase was adjusted to a mixture of 5:1 heptane-ethyl acetate, and then adjusted to a mixture of 7:3 heptane-ethyl acetate to provide 800 mg (50% yield) of the desired product as an off-white foam. The structure was confirmed by 1H NMR analysis in DMSO-d6.

Workup

  1. customwas prepared in a 100-mL 2-necked round-bottomed flask
  2. customfitted with a reflux condenser
  3. temperaturethe reaction mixture was heated
  4. temperatureat reflux
  5. customProgress of the reaction was monitored by HPLC analysis of reaction aliquots
  6. temperatureAfter 15 h of reflux the reaction
  7. customwas consumed
  8. filtrationfiltered
  9. customto remove inorganic salts
  10. concentrationThe filtrate was concentrated by rotoevaporation
  11. customto provide 2.2 g of a crude oil
  12. customThe crude product was purified by flash chromatography on silica gel using an initial mobile phase
  13. additionconsisting of a mixture of 9:1 heptane-ethyl acetate
  14. additionThe mobile phase was adjusted to a mixture of 5:1 heptane-ethyl acetate
  15. additionadjusted to a mixture of 7:3 heptane-ethyl acetate

Sources & evidence

ORD record
ord-465249878c4648258a17fd487f2bca46
Source dataset
uspto-grants-2012_01
Patent number
US08106052B2

Reaction notes

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