Iodine → 4-Fluoro-7-methoxy-1-benzothiophene-2-carboxylic acid

HRID 2220298Notes

Reaction equation

HRID 2220298 reaction equation
[F:1][C:2]1[CH:7]=[CH:6][C:5]([O:8][CH3:9])=[CH:4][C:3]=1/[CH:10]=[C:11](\[SH:15])/[C:12]([OH:14])=[O:13].II.S(S([O-])=O)([O-])(=O)=O.[Na+].[Na+].CCOCC>C(COC)OC>[F:1][C:2]1[C:3]2[CH:10]=[C:11]([C:12]([OH:14])=[O:13])[S:15][C:4]=2[C:5]([O:8][CH3:9])=[CH:6][CH:7]=1

Participants

6

Reactant 4

HCID 807IodineHCID 3283Diethyl EtherHCID 656671Sodium PyrosulfiteHCID 58630707(2Z)-3-(2-Fluoro-5-methoxyphenyl)-2-mercapto-2-propenoic acid

Product 1

HCID 235689524-Fluoro-7-methoxy-1-benzothiophene-2-carboxylic acidYield 58.5%

Reagents, catalysts & solvents 1

HCID 80711,2-DimethoxyethaneSolvent

Procedure

(2Z)-3-(2-Fluoro-5-methoxyphenyl)-2-mercapto-2-propenoic acid (1.00 g, 4.38 mmol) was added in one portion to a solution of iodine (1.66 g, 6.56 mmol) in dimethoxyethane (10 mL). This was heated in the microwave with 300W at 160° C. for 10 mins. After this time the reaction was allowed to cool to room temperature and poured onto saturated sodium metabisulphite (200 mL) and ether (400 mL). Ether layer was separated and product extracted with aqueous sodium hydroxide (2 N, 2×100 mL). This was then acidified to pH 2 with aqueous hydrochloric acid (2 N, 250 mL), and product extracted with ether (2×150 mL). The combined organic extracts were dried (MgSO4) and concentrated in vacuo to give a white solid (580 mg, 30%); δH (300 MHz, CD3OD) 8.00 (1H, s, Ar), 7.30-7.19 (1H, m, Ar), 7.10-7.00 (1H, m, Ar), 3.95 (3H, s, OCH3).

Workup

  1. customEther layer was separated
  2. extractionproduct extracted with aqueous sodium hydroxide (2 N, 2×100 mL)
  3. extractionextracted with ether (2×150 mL)
  4. dry with materialThe combined organic extracts were dried (MgSO4)
  5. concentrationconcentrated in vacuo

Sources & evidence

ORD record
ord-290dc7e7d0e84f199a3eb5de3ca82a14
Source dataset
uspto-grants-2008_08
Patent number
US07417064B2

Reaction notes

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