Hydrochloric Acid → HCID 18694168, compound

HRID 399918Notes

Reaction equation

HRID 399918 reaction equation
[F:1][C:2]1[CH:3]=[C:4](I)[C:5]2[O:10][CH:9]([C:11]([O:13][CH3:14])=[O:12])[CH2:8][CH2:7][C:6]=2[CH:15]=1.[F:17][C:18]([Si](C)(C)C)([F:20])[F:19].[F-].[K+].Cl.O>CN(C=O)C.CN1CCCC1=O.[Fe](Cl)(Cl)Cl>[F:1][C:2]1[CH:3]=[C:4]([C:18]([F:20])([F:19])[F:17])[C:5]2[O:10][CH:9]([C:11]([O:13][CH3:14])=[O:12])[CH2:8][CH2:7][C:6]=2[CH:15]=1

Participants

9

Reactant 5

HCID 313Hydrochloric AcidHCID 962WaterHCID 522689Potassium FluorideHCID 552549(Trifluoromethyl)trimethylsilaneHCID 18694182HCID 18694182, compound

Product 1

HCID 18694168HCID 18694168, compoundYield 16.6%

Reagents, catalysts & solvents 3

HCID 24380Iron chloride (FeCl3)CatalystHCID 6228DimethylformamideSolventHCID 13387N-methyl-2-pyrrolidoneSolvent

Conditions

Temperature
60 °C

Procedure

A suspension of (±)-methyl 6-fluoro-3,4-dihydro-8-iodo-2H-1-benzopyran-2-carboxylate (0.026 mol), (trifluoromethyl)trimethylsilane (0.081 mol), cuprous iodide (0.1 mol) and kalium fluoride (0.081 mol) in a mixture of DMF (50 ml) and 1-methyl-2-pyrrolidinone (50 ml) was stirred for 3 h at 60° C. The cooled reaction mixture was poured out into a solution of iron (III) chloride (200 g) and hydrochloric acid (50 ml) in water (300 mol). This mixture was extracted three times with diethyl ether (150 ml). The combined organic layers were washed with a 5% aqueous Na2S2 O3 solution (decolorization), dried (MgSO4), filtered and the solvent was evaporated. The residue was purified by flash column chromatography over silica gel (eluent: CH2Cl2). The pure fractions were collected and the solvent was evaporated, yielding 5.7 g (78.8%). This fraction was recrystallized from DIPE. The precipitate was filtered off and dried, yielding 1.2 g (16.6%) (±)-methyl 6-fluoro-3,4-dihydro-8-(trifluoromethyl)-2H-1-benzopyran-2-carboxylate; mp. 71.8° C. (interm 4-b).

Workup

  1. customThe cooled reaction mixture
  2. extractionThis mixture was extracted three times with diethyl ether (150 ml)
  3. washThe combined organic layers were washed with a 5% aqueous Na2S2 O3 solution (decolorization)
  4. dry with materialdried (MgSO4)
  5. filtrationfiltered
  6. customthe solvent was evaporated
  7. customThe residue was purified by flash column chromatography over silica gel (eluent: CH2Cl2)
  8. customThe pure fractions were collected
  9. customthe solvent was evaporated
  10. customyielding 5.7 g (78.8%)
  11. customThis fraction was recrystallized from DIPE
  12. filtrationThe precipitate was filtered off
  13. customdried

Sources & evidence

ORD record
ord-c187e181f3c246a2858c9f02bfc271a2
Source dataset
uspto-grants-1998_10
Patent number
US05824682

Reaction notes

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