Lithium iodide → 6-(4-hydroxyphenyl)thio-2,2,3-trimethyl-2H-benzo[b]pyran

HRID 1416180Notes

Reaction equation

HRID 1416180 reaction equation
C[O:2][C:3]1[CH:8]=[CH:7][C:6]([S:9][C:10]2[CH:22]=[CH:21][C:13]3[O:14][C:15]([CH3:20])([CH3:19])[C:16]([CH3:18])=[CH:17][C:12]=3[CH:11]=2)=[CH:5][CH:4]=1.[I-].[Li+]>N1C(C)=CC(C)=CC=1C.ClCCl>[OH:2][C:3]1[CH:4]=[CH:5][C:6]([S:9][C:10]2[CH:22]=[CH:21][C:13]3[O:14][C:15]([CH3:19])([CH3:20])[C:16]([CH3:18])=[CH:17][C:12]=3[CH:11]=2)=[CH:7][CH:8]=1

Participants

5

Reactant 2

HCID 66321Lithium iodide2×HCID 187828716-(4-methoxyphenyl)thio-2,2,3-trimethyl-2H-benzo[b]pyran

Product 1

HCID 187828866-(4-hydroxyphenyl)thio-2,2,3-trimethyl-2H-benzo[b]pyranYield 77.7%

Reagents, catalysts & solvents 2

HCID 6344DichloromethaneSolventHCID 79532,4,6-TrimethylpyridineSolvent

Procedure

6-(4-Methoxyphenyl)thio-2,2,3-trimethyl-2H-benzo[b]pyran (7.816 g) (see Preparation 5) was dissolved in dry 2,4,6-collidine (30 ml), anhydrous lithium iodide (10.04 g) was added and the mixture was heated under reflux under.a nitrogen atmosphere for 48 hours. A further portion of lithium iodide (9.06. g) was then added and heating was continued for another 72 hours. After cooling, the mixture was taken up in dichloromethane and washed with 2N aqueous hydrochloric acid solution (×3). The organic layer was separated, dried (anhydrous sodium sulphate), the solvent removed under reduced pressure and the residue was chromatographed on silica using dichloromethane as the eluent to yield 6-(4-hydroxyphenyl)thio-2,2,3-trimethyl-2H-benzo[b]pyran (5.799 g) as an oil.

Workup

  1. temperaturethe mixture was heated
  2. temperatureunder reflux under.a nitrogen atmosphere for 48 hours
  3. temperatureheating
  4. temperatureAfter cooling
  5. washwashed with 2N aqueous hydrochloric acid solution (×3)
  6. customThe organic layer was separated
  7. dry with materialdried (anhydrous sodium sulphate)
  8. customthe solvent removed under reduced pressure
  9. customthe residue was chromatographed on silica

Sources & evidence

ORD record
ord-a2eb95c7ed4340b985e636263d4b6c51
Source dataset
uspto-grants-1999_06
Patent number
US05912244

Reaction notes

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