Trifluoroacetic anhydride → HCID 22394204, compound

HRID 1419084Notes

Reaction equation

HRID 1419084 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

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-ab67c16ccc72475bb0658cc1ebe88ebc
Source dataset
uspto-grants-1999_03
Patent number
US05886016

Reaction notes

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