Hydrogen Bromide → HCID 20296847, compound

HRID 1389541Notes

Reaction equation

HRID 1389541 reaction equation
C[O:2][C:3]1[CH:4]=[C:5]([CH:16]=[CH:17][C:18]=1[CH3:19])[C:6]([C:8]1[CH:13]=[CH:12][C:11]([O:14]C)=[CH:10][CH:9]=1)=[O:7].Br.C(OC(=O)C)(=O)C>C(O)(=O)C>[OH:2][C:3]1[CH:4]=[C:5]([CH:16]=[CH:17][C:18]=1[CH3:19])[C:6]([C:8]1[CH:9]=[CH:10][C:11]([OH:14])=[CH:12][CH:13]=1)=[O:7]

Participants

5

Reactant 3

HCID 260Hydrogen BromideHCID 7918Acetic AnhydrideHCID 20296846HCID 20296846, compound

Product 1

HCID 20296847HCID 20296847, compoundYield 77.8%

Reagents, catalysts & solvents 1

HCID 176Acetic AcidSolvent

Procedure

Demethylation of 114 g 3,4'-dimethoxy-4-methyl-benzophenone (0.445 mole) was effected by refluxing 15 hr. with a previously prepared mixture of 313.5 ml of 48% aqueous hydrobromic acid, 148 ml of acetic anhydride, and 148 ml of acetic acid. The isolated product melted at 173°-174° C. Recrystallization from ethanol/water yielded 79 g (0.346 mole) of 3,4'-dihydroxy-4-methylbenzophenone melting at 174°-175° C.

Workup

  1. temperatureby refluxing 15 hr
  2. customRecrystallization from ethanol/water

Sources & evidence

ORD record
ord-25e81c0b1184470dab71e9a1bf8d69c9
Source dataset
uspto-grants-1981_01
Patent number
US04245082

Reaction notes

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