US4476318A
Expired / Lapsed
US
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Process for the preparation of 1,3-propanediol bis(p-aminobenzoate)
Assignee: Ihara Chemical Industry Co Ltd
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Filing: 1982-09-29
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Granted: 1984-10-09
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Expires: 2002-09-29
Abstract
Abstract A process for the preparation of 1,3-propanediol bis(p-aminobenzoate) is described, comprising reacting a p-aminobenzoic acid alkali metal salt with dihalogenated propane in an aprotic polar solvent. In accordance with this process, diesterification proceeds under mild conditions without causing any undesirable side reactions and, therefore the desired 1,3-propanediol bis(p-aminobenzoate) can be obtained in high purity and high yield.
Inventors
- 👤 Takao Harada
- 👤 Chihiro Yazawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 15:27
CPC Classifications
C; C07; C07C; C07C227/00; C07C227/14; C07C227/18
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
75 words
A process for preparing 1,3-propanediol bis(p-aminobenzoate) represented by formula (III): ##STR4## comprising reacting (i) a p-aminobenzoic acid alkali metal salt represented by formula (I): ##STR5## (wherein M is an alkali metal atom) with (ii) dihalogenated propane represented by formula (II): X--CH.sub.2 CH.sub.2 CH.sub.2 --Y (II) (wherein X and Y may be the same or different, and are halogen atoms), in an aprotic polar solvent and at a temperature of from 60° C. to 150° C.
Claim 2
Dependent Claim
75 words
A process for preparing 1,3-propanediol bis(p-aminobenzoate) represented by formula (III): ##STR4## comprising reacting (i) a p-aminobenzoic acid alkali metal salt represented by formula (I): ##STR5## (wherein M is an alkali metal atom) with (ii) dihalogenated propane represented by formula (II): X--CH.sub.2 CH.sub.2 CH.sub.2 --Y (II) (wherein X and Y may be the same or different, and are halogen atoms), in an aprotic polar solvent and at a temperature of from 60° C. to 150° C.
Claim 3
Dependent Claim
27 words
A process for preparing 1,3-propanediol bis(p-aminobenzoate) as claimed in claim 1, wherein the reaction is carried out at a temperature of from 80° C. to 130° C.
Claim 4
Dependent Claim
27 words
A process for preparing 1,3-propanediol bis(p-aminobenzoate) as claimed in claim 2, wherein the reaction is carried out over a period of from 1 hour to 6 hours.
Claim 5
Dependent Claim
42 words
A process for preparing 1,3-propanediol bis(p-aminobenzoate) as claimed in any one of claims 1 or 3, wherein the aprotic polar solvent is present in an amount of 3 to 5 times by weight the amount of the p-aminobenzoic acid alkali metal salt.
References Cited (Backward Citations)
US4058550A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-10-09 | 1988-04-09 | 1988-10-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-10-09 | 1992-04-09 | 1992-10-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-10-09 | 1996-04-09 | 1996-10-09 | $7700.00 | Window Closed / Lapsed |