Trifluoroacetic anhydride → HCID 22394204, compound

HRID 1379142Notes

Reaction equation

HRID 1379142 reaction equation
[Cl:1][C:2]1[CH:3]=[C:4]([CH:11]=[CH:12][CH:13]=1)[CH2:5][S:6][CH2:7][C:8](O)=[O:9].FC(F)(F)C(OC(=O)C(F)(F)F)=O.C([O-])([O-])=O.[Na+].[Na+]>FC(F)(F)C(O)=O>[Cl:1][C:2]1[CH:3]=[C:4]2[C:11]([C:8](=[O:9])[CH2:7][S:6][CH2:5]2)=[CH:12][CH:13]=1

Participants

5

Reactant 3

HCID 9845Trifluoroacetic anhydrideHCID 10340Sodium CarbonateHCID 2115231{[(3-Chlorophenyl)methyl]sulfanyl}acetic acid

Product 1

HCID 22394204HCID 22394204, compoundYield 51.1%

Reagents, catalysts & solvents 1

HCID 6422Trifluoroacetic acidSolvent

Procedure

3-Chlorobenzylmercaptoacetic acid from Step 2 (3.35 g) was dissolved in trifluoroacetic acid (50 mL). Trifluoroacetic acid anhydride (25 mL) was added and the reaction stirred at reflux, under a nitrogen atmosphere for 16 hours. The solution was carefully poured into 10% Na2CO3 solution (500 mL) which was stirring vigorously. The organics were extracted into ether (500 mL) and washed with brine (300 mL), dried over MgSO4 and concentrated in vacuo. The resulting brown solid was purified by silica gel chromatography eluting with a 0-10% gradient of ethyl acetate in hexane to yield 7-chloroisothiochroman-4-one (1.57 g, 51%): 1H NMR (CDCl3) δ=3.49p (d, 2H, J=0.8 Hz), 3.8p (s, 2H), 7.16p (m, 1H), 7.3p (dd, 1H, J=2.0, 8.4 Hz), 7.96p (d, 1H, J=8.5 Hz).

Workup

  1. temperatureat reflux, under a nitrogen atmosphere for 16 hours
  2. stirringwas stirring vigorously
  3. extractionThe organics were extracted into ether (500 mL)
  4. washwashed with brine (300 mL)
  5. dry with materialdried over MgSO4
  6. concentrationconcentrated in vacuo
  7. customThe resulting brown solid was purified by silica gel chromatography
  8. washeluting with a 0-10% gradient of ethyl acetate in hexane

Sources & evidence

ORD record
ord-d06243b641da4d5aaffa5e1260e357ae
Source dataset
uspto-grants-1997_09
Patent number
US05670532

Reaction notes

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