US 6,831,201 B2Granted

Process for producing diphenyl sulfone compound

AssigneeNippon Soda Co., Ltd.

InventorsKiyoshi Katsuura, Tomoya Hidaka, Yutaka Takashina, Yasuo Ohnuki

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Abstract

The present invention is to provide methods for producing highly pure 4,4′-dihydroxydiphenyl sulfone monoethers advantageously in industrial production. In a process for producing a compound represented by Formula (1) (wherein, R1 and R2 are each independently halogen, alkyl having 1 to 8 carbons or alkenyl having 2 to 8 carbons; m and n are each independently 0 or an integer of 1 to 4; and R3 is alkyl having 1 to 8 carbons, alkenyl having 2 to 8 carbons, cycloalkyl having 3 to 8 carbons or optionally substituted aralkyl), (1) a pH adjustment is carried out twice or more in the purification process, (2) an excessive amount of alkyl halide used is removed, (3) a solvent, such as water, containing 0.05 ppm or less of iron components is used, (4) tanks with corrosion-resistant layers over the inner walls are used, (6) a chelating agent is added, and (7) a means of drying with mechanical stir is applied.

Claims5

Dependent claims

A process for the purification of a compound represented by Formula (I)

wherein, R1 and R2 are each independently halogen, alkyl having 1 to 8 carbons or alkenyl having 2 to 8 carbons;
m and n are each independently 0 or an integer of 1 to 4;
and R3 is alkyl having 1 to 8 carbons, alkenyl having 2 to 8 carbons, cycloalkyl having 3 to 8 carbons or optionally substituted aralkyl, in which the process comprises:
adjusting a pH of an aqueous solution containing a compound of Formula (I) to a preset value (P1) between about 8.0 and 9.0,
then extracting said pH adjusted aqueous solution using a water-nonmiscible organic solvent, and
separating said extracted aqueous solution to an organic layer and an aqueous layer, wherein the compound of Formula (I) is in the separated organic layer and wherein the preset value (P1) is such as to facilitate the inclusion of the compound of Formula (I) in the separated organic layer, and
adding a water to the separated organic layer, and adjusting the pH of the aqueous layer to a preset value (P2) between about 8.3 and 8.6,
wherein the compound of Formula (I) is in the separated organic layer and wherein the preset value (P2) is such as to facilitate the inclusion of the compound of Formula (I) in the separated organic layer.

5 more elements

Dependencies are inferred from the claim text.

Facts

Application: 10/239,483Filed 20 Sep 2002
Priority: JP 2001-01363822 Jan 2001
Published: US 2003/0092941 A115 May 2003
Granted: 14 Dec 2004
Term ends: Not estimatedThe source records don’t support an estimate.

Classification3 codes

C07C 315/04
Preparation of sulfones; Preparation of sulfoxides: by reactions not involving the formation of sulfone or sulfoxide groups
C07C 315/06
Preparation of sulfones; Preparation of sulfoxides: separation; Purification; Stabilisation; Use of additives
C07C
Acyclic or carbocyclic compounds