Methanesulfonic Acid → 3-Bromo-7,9-dimethoxy-10,11-dihydrodibenz[b,f]oxepin-10-one

HRID 48010Notes

Reaction equation

HRID 48010 reaction equation
[Br:1][C:2]1[CH:7]=[CH:6][C:5]([CH2:8][C:9]([OH:11])=O)=[C:4]([O:12][C:13]2[CH:18]=[C:17]([O:19][CH3:20])[CH:16]=[C:15]([O:21][CH3:22])[CH:14]=2)[CH:3]=1.CS(O)(=O)=O>>[Br:1][C:2]1[CH:7]=[CH:6][C:5]2[CH2:8][C:9](=[O:11])[C:14]3[C:15]([O:21][CH3:22])=[CH:16][C:17]([O:19][CH3:20])=[CH:18][C:13]=3[O:12][C:4]=2[CH:3]=1

Participants

3

Reactant 2

HCID 6395Methanesulfonic AcidHCID 23431850HCID 23431850, compound2×

Product 1

HCID 234318523-Bromo-7,9-dimethoxy-10,11-dihydrodibenz[b,f]oxepin-10-oneYield 66%

Conditions

Temperature
40 °C

Procedure

To 27.3 g (F.W. 367.195, 74.3 mmol) of carboxylic acid (26) was added 140 mL of methanesulfonic acid to dissolve carboxylic acid (26). This solution was stirred at 40° C. for three days. To the resulting reaction solution was added 300 mL of ice water to deposit a cyclized compound. The cyclized compound was separated by filtration and extracted with ethyl acetate and treated according to the conventional method to obtain a crude product. This crude product was purified by silica gel column chromatography (developing solvent; ethyl acetate:hexane=1:2) and recrystallized from hexane-ethyl acetate to obtain 17.1 g (66%) of cyclized compound (27). (TLC; ethyl acetate:hexane=1:2).

Workup

  1. customTo the resulting reaction solution
  2. customThe cyclized compound was separated by filtration
  3. extractionextracted with ethyl acetate
  4. additiontreated
  5. customto obtain a crude product
  6. customThis crude product was purified by silica gel column chromatography (developing solvent; ethyl acetate:hexane=1:2)
  7. customrecrystallized from hexane-ethyl acetate

Sources & evidence

ORD record
ord-c4ecd3729f1d48568939e0d65c0c6843
Source dataset
uspto-grants-2004_03
Patent number
US06700013B2

Reaction notes

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