Diisopropylethylamine → 5-Bromo-thiophene-2-sulfonic acid 6-chloro-2-oxo-2H-1-benzopyran-4-yl ester

HRID 495143Notes

Reaction equation

HRID 495143 reaction equation
[Cl:1][C:2]1[CH:3]=[C:4]2[C:9](=[CH:10][CH:11]=1)[O:8][C:7](=[O:12])[CH:6]=[C:5]2[OH:13].CCN(C(C)C)C(C)C.[Br:23][C:24]1[S:28][C:27]([S:29](Cl)(=[O:31])=[O:30])=[CH:26][CH:25]=1>C(Cl)Cl>[Cl:1][C:2]1[CH:11]=[CH:10][C:9]2[O:8][C:7](=[O:12])[CH:6]=[C:5]([O:13][S:29]([C:27]3[S:28][C:24]([Br:23])=[CH:25][CH:26]=3)(=[O:31])=[O:30])[C:4]=2[CH:3]=1

Participants

5

Reactant 3

HCID 81531DiisopropylethylamineHCID 27339245-Bromothiophene-2-sulfonyl chlorideHCID 546863486-Chloro-4-hydroxycoumarin

Product 1

HCID 117505475-Bromo-thiophene-2-sulfonic acid 6-chloro-2-oxo-2H-1-benzopyran-4-yl esterYield 21.3%

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent

Conditions

Temperature
0 °C

Procedure

6-Chloro-4-hydroxycoumarin (0.5 mmol, 0.099 g) is suspended in 5 mL of DCM, and enough DIEA is added to bring the pH to 9 as measured by pH paper. The solution is cooled to 0° C., and 5-bromo-thiophene-2-sulfonyl chloride (0.5 mmol, 0.13 g) is added. The solution is warmed to ambient temperature and is stirred 2 hrs. The solvent is removed under reduced pressure and the residue is triturated with Et2O. The resulting solid is filtered, is washed with Et2O, and is dried to afford the title compound (45 mg, 21%). 1H NMR (CDCl3, 300 MHz) δ 7.65 (1H, d, J=4.25 Hz), 7.56 (2H, m), 7.29 (1H, d, J=8.75 Hz), 7.19 (1H, d, J=4.25 Hz), 6.48 (1H, s), MS (ESI, Pos.) calcd for C13H6BrClO5S2 m/z [M+H]=420.9, found 420.9.

Workup

  1. temperatureThe solution is warmed to ambient temperature
  2. customThe solvent is removed under reduced pressure
  3. customthe residue is triturated with Et2O
  4. filtrationThe resulting solid is filtered
  5. washis washed with Et2O
  6. customis dried

Sources & evidence

ORD record
ord-00e03d21effa402ea30e376f61c5da5e
Source dataset
uspto-grants-2009_05
Patent number
US07538233B2

Reaction notes

Loading…