Sulfuric Acid → 2-Bromo-7-methoxy-9H-xanthen-9-one

HRID 1851632Notes

Reaction equation

HRID 1851632 reaction equation
[Br:1][C:2]1[CH:19]=[CH:18][C:5]([O:6][C:7]2[CH:15]=[CH:14][C:13]([O:16][CH3:17])=[CH:12][C:8]=2[C:9]([OH:11])=O)=[CH:4][CH:3]=1.S(=O)(=O)(O)O>>[Br:1][C:2]1[CH:3]=[CH:4][C:5]2[O:6][C:7]3[C:8](=[CH:12][C:13]([O:16][CH3:17])=[CH:14][CH:15]=3)[C:9](=[O:11])[C:18]=2[CH:19]=1

Participants

3

Reactant 2

HCID 1118Sulfuric AcidHCID 574756322-(4-Bromophenoxy)-5-methoxybenzoic acid

Product 1

HCID 574756332-Bromo-7-methoxy-9H-xanthen-9-oneYield 259.8%

Procedure

To 2-(4-bromophenoxy)-5-methoxybenzoic acid (530 g, 1.6401 mol) was added sulfuric acid (1.6 lit, 3 vol.) at RT. The resulting dark mixture was heated to 60 C. TLC showed complete conversion of starting material to product after about 1 hr. The brown solution was cooled to RT and poured onto ice with manual stirring. The resulting tan precipitate was collected by filtration, washed with water, 1N NaOH (2.0 lit) solution and finally with 800 mL of ethanol & stirred in 2 liters of acetone & filtered. The solids were dried under vacuum to afford 1.3 kg (68.85%) of the titled compounds as a white solid. MS m/z=307.0 [M+H]+. Calc'd for C14H9BrO3: 305.1.

Workup

  1. temperatureThe resulting dark mixture was heated to 60 C
  2. customafter about 1 hr
  3. additionpoured onto ice with manual stirring
  4. filtrationThe resulting tan precipitate was collected by filtration
  5. washwashed with water, 1N NaOH (2.0 lit) solution and finally with 800 mL of ethanol
  6. filtrationfiltered
  7. customThe solids were dried under vacuum

Sources & evidence

ORD record
ord-2cd2323bc2ce4d00abb014f0549bb073
Source dataset
uspto-grants-2015_02
Patent number
US08957083B2

Reaction notes

Loading…