Claims
- 1. A process for the preparation of a salt of 2-carboxy-anthraquinone monosulfonic acid of the general formula ##STR13## wherein M is sodium, potassium or an ammonium group, characterized in that benzophenone-2,4-dicarboxylic acid, benzophenone-2,5-dicarboxylic acid or 2-(p-carboxybenzoyl) benzoic acid is heated in fuming sulfuric acid whereby dehydration and sulfonation are effected in one step without isolation.
- 2. A process according to claim 1 wherein a mixture of benzophenone-2,4-dicarboxylic acid and benzophenone-2,5-dicarboxylic acid is heated in fuming sulfuric acid whereby dehydration and sulfonation are effected in one step without isolation.
- 3. A process for the preparation of a salt of 2-phenoxy anthraquinone polysulfonic acid of the general formula ##STR14## wherein M is sodium, potassium or an ammonium group and n is an integer of 1 or 2,
- characterized in that 2-(p-phenoxybenzoyl) benzoic acid is heated together with (a) a hydrating agent selected from the group consisting of fuming sulfuric acid, sulfuric acid, sulfur trioxide, polyphosphoric acid and phosphorus pentoxide and (b) a sulfonating agent selected from the group consisting of sulfuric acid, fuming sulfuric acid, sulfur trioxide and chlorosulfonic acid, whereby dehydration and sulfonation are effected in one step without isolation.
- 4. A process according to claim 3 where 2-(p-phenoxybenzoyl) benzoic acid is heated in fuming sulfuric acid to effect dehydration and sulfonation.
Priority Claims (1)
Number |
Date |
Country |
Kind |
53-58878 |
May 1978 |
JPX |
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Parent Case Info
This is a division of application Ser. No. 26,934 filed Apr. 4, 1979, now U.S. Pat. No. 4,276,187.
US Referenced Citations (4)
Number |
Name |
Date |
Kind |
1917421 |
Baumann et al. |
Jul 1933 |
|
3089879 |
Sevves et al. |
May 1963 |
|
3280154 |
Hopff et al. |
Oct 1966 |
|
3933917 |
Schaffner et al. |
Jan 1976 |
|
Foreign Referenced Citations (3)
Number |
Date |
Country |
149721 |
Aug 1973 |
CSX |
149998 |
Aug 1973 |
CSX |
150000 |
Aug 1973 |
CSX |
Divisions (1)
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Number |
Date |
Country |
Parent |
26934 |
Apr 1979 |
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