Process for producing pyrogallol and derivatives thereof
AssigneeMitsubishi Chemical Industries Limited
InventorsHeitaro Obara, Junichi Onodera, Akira Matukuma, Kenji Yoshida
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Abstract
A process for producing pyrogallol or 5-substituted pyrogallol having the formula: ##SPC1## Wherein R is selected from the group consisting of alkyl, cycloalkyl, aryl, and aralkyl, or a mixture thereof which comprises heating an aqueous solution of 4-substituted-2,6-diaminophenol or 4-substituted-2,6-diamino 1-alkoxybenzene having the formula: ##SPC2## Wherein R is as defined above and A is selected from the group consisting of hydrogen and alkyl, under acid conditions.
Claims10
A process for producing pyrogallol, which comprises:
- heating an aqueous solution of 4-substituted-2,6-diamino-phenol or 4-substituted-2,6-diamino-1-alkoxy benzene having the formula:
- ##SPC5##
- wherein R is alkyl, cycloalkyl, or aralkyl, respectively, having from 1 to 10 carbon atoms and having a tertiary carbon atom bonded directly to the nuclear benzene carbon atom, and A is hydrogen or alkyl, having from 1 to 10 carbon atoms at a temperature of 150.degree.-300.degree.C in the presence of hydrochloric acid, hydrobromic acid, sulfuric acid, phosphoric acid, methane sulfonic acid or trifluoromethane sulfonic acid.
A process for producing pyrogallol, which comprises:
- heating an aqueous solution containing 0.5 - 12 wt% of 4-substituted-2,6-diaminophenol or 4-substituted-2,6-diamino-1-alkoxybenzene having the formula:
- ##SPC6##
- wherein R is alkyl, cycloalkyl, or aralkyl, respectively, having from 1-10 carbon atoms and having a tertiary carbon atom which is bonded directly to the nuclear benzene carbon atom, and A is hydrogen or alkyl having not more than 10 carbon atoms, at a temperature of 150.degree.-300.degree.C in the presence of hydrochloric acid, hydrobromic acid, sulfuric acid, phosphoric acid, methane sulfonic acid or trifluoromethane sulfonic acid under an atmosphere of an inert gas selected from the group consisting of hydrogen, nitrogen, carbon dioxide, helium, and argon, for a time sufficient to effect substantial conversion thereof.
Dependencies are inferred from the claim text.