Xanthene → Xanthone

HRID 1076900

Reaction equation

HRID 1076900 reaction equation
[Cr](O[Cr]([O-])(=O)=O)([O-])(=O)=O.[Cr](O[Cr]([O-])(=O)=O)([O-])(=O)=O.[Na+].[Na+].[Cr](O[Cr]([O-])(=O)=O)([O-])(=O)=[O:22].[K+].[K+].[CH:32]1[C:45]2[CH2:44][C:43]3[C:38](=[CH:39][CH:40]=[CH:41][CH:42]=3)[O:37][C:36]=2[CH:35]=[CH:34][CH:33]=1>C(O)(=O)C.C(O)(C)(C)C.O>[CH:32]1[C:45]2[C:44](=[O:22])[C:43]3[C:38](=[CH:39][CH:40]=[CH:41][CH:42]=3)[O:37][C:36]=2[CH:35]=[CH:34][CH:33]=1

Participants

8

Reactant 4

HCID 7107Xanthene2×HCID 24502Potassium DichromateHCID 24503Dichromate ionHCID 25408Sodium Dichromate2×

Product 1

HCID 7020Xanthone

Reagents, catalysts & solvents 3

HCID 176Acetic AcidSolvent2×HCID 962WaterSolventHCID 6386tert-ButanolSolvent

Procedure

The above oxidation reaction may be carried out using dichromate anion such as sodium dichromate or potassium dichromate as the oxidizing agent. The reaction will proceed in from 15 minutes to 6 hours at a temperature of from 80° to 120°C. The amount of oxidizing agent is limited to the stoichiometric quantity required for oxidation of the 9-methylene group of the xanthene derivative. Suitable solvents for this conversion are, for example, water, acetic acid, tert-butyl alcohol, and the like, or combinations of these solvents. For example, by combining three moles of the xanthene derivative, Formula II, dissolved in acetic acid with four moles of sodium dichromate and refluxing the mixture for 1 to 3 hours, the corresponding xanthen-9-one derivative, Formula III, can be obtained.

Workup

  1. customThe above oxidation reaction
  2. customThe reaction
  3. customwill proceed in from 15 minutes to 6 hours at a temperature of from 80° to 120°C
  4. temperaturerefluxing the mixture for 1 to 3 hours

Sources & evidence

ORD record
ord-c3c3123c34a842918312ec9639ac1e9c
Source dataset
uspto-grants-1976_05
Patent number
US03957989

Linked notes

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