Sulfuric Acid → 8-(Trifluoromethyl)-2,3-dihydro-4H-1-benzopyran-4-one

HRID 536458Notes

Reaction equation

HRID 536458 reaction equation
Cl[C:2]#[C:3][CH2:4][O:5][C:6]1[CH:11]=[CH:10][CH:9]=[CH:8][C:7]=1[C:12]([F:15])([F:14])[F:13].S(=O)(=O)(O)[OH:17]>FC(F)(F)C(O)=O>[F:13][C:12]([F:15])([F:14])[C:7]1[CH:8]=[CH:9][CH:10]=[C:11]2[C:6]=1[O:5][CH2:4][CH2:3][C:2]2=[O:17]

Participants

4

Reactant 2

HCID 1118Sulfuric AcidHCID 534868451-[(3-Chloroprop-2-yn-1-yl)oxy]-2-(trifluoromethyl)benzene

Product 1

HCID 426145998-(Trifluoromethyl)-2,3-dihydro-4H-1-benzopyran-4-oneYield 32.4%

Reagents, catalysts & solvents 1

HCID 6422Trifluoroacetic acidSolvent

Procedure

A solution of Example 18A (24.1 g, 103 mmol) and sulfuric acid (12 mL, 225 mmol) in trifluoroacetic acid (200 mL) was stirred at room temperature for 3 days. The reaction mixture was poured into ice-water and extracted with dichloromethane (2×200 mL). The organic layers were combined, washed with a saturated aqueous NaHCO3 solution (200 mL), dried (MgSO4), filtered, and concentrated. Silica gel chromatography (15% EtOAc/hexanes) gave the title compound (7.21 g, 33.4 mmol, 32%). MS (DCI/NH3) m/z 216 (M+NH4—H2O)+.

Workup

  1. extractionextracted with dichloromethane (2×200 mL)
  2. washwashed with a saturated aqueous NaHCO3 solution (200 mL)
  3. dry with materialdried (MgSO4)
  4. filtrationfiltered
  5. concentrationconcentrated

Sources & evidence

ORD record
ord-4e86223f764c4ed6a01ffa7fd5145728
Source dataset
uspto-grants-2014_10
Patent number
US08859584B2

Reaction notes

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