Indian Patents. 225931:A PROCESS TO MANUFACTURE 2-ETHOXY BENZOIC ACID

Title of Invention	A PROCESS TO MANUFACTURE 2-ETHOXY BENZOIC ACID
Abstract	The present invention relates to a process of preparation of 2 Ethoxy Benzoic Acid comprising the steps of i)reacting Salicylic Acid with diethyl sulphate and a quaternary ammonium salt in the presence of an alkali hydroxide solution.ii)reacting the resultant with an alkali hydroxide solution and iii)reacting the resultant with mineral acid.

Full Text	FORM 2 THE PATENTS ACT, 1970 (39 OF 1970) & THE PATENT RULES, 2003 COMPLETE SPECIFICATION [SECTION 10 AND RULE 13] "A PROCESS TO MANUFACTURE 2-ETHOXY BENZOIC ACID" APPLICANT: GUJARAT ORGANICS LIMITED NATIONALITY: AN INDIAN COMPANY INCORPORATED UNDEF ADDRESS: THE COMPANIES ACT, 1956. PLOT NO. 127/1, GIDC ESTATE, ANKLESHWAR 393 002, DIST.BHARUCH, GUJARAT STATE, INDIA. THE FOLLOWING SPECIFICATION PARTICULARLY DESCRIBES THE NATURE OF THIS INVENTION AND THE MANNER IN WHICH IT IS TO BE PERFORMED: Field of Invention The present invention relates to a process of preparing 2-Ethoxy Benzoic Acid. The disclosure describes an economical method of preparing 2-Ethoxy Benzoic Acid free of Salicylic Acid impurity. Background In the prior art, 2-Ethoxy Benzoic Acid is prepared in two steps from Salicylamide. Firstly, Salicylamide in aqueous alkaline solution is reacted with Di Ethyl Sulphate to yield ether amide (2-Ethoxy Benzamide). As a second step, the said amide is hydrolyzed in situ by addition of alkali hydroxide and heating it. The resulting 2-Ethoxy Benzoic Acid sodium salt is treated with mineral acid to liberate 2-Ethoxy Benzoic Acid as oil. The oil is separated and washed with water. Traces of water in the product are removed as Ethylene Dichloride water azeotrope. Further, careful vacuum distillation of the product results in 2-Ethoxy Benzoic Acid (135°C-138°C / 0.5 mmHg) with Salicylic acid impurity of 3-4 %. 2-Ethoxy Benzoic Acid is cleaved to Salicylic Acid in the presence of moisture and acidity. The drawbacks of prior art is that the raw material Salicylamide is obtained after three steps and overall yields are low (65%)., based on theory. The material has high level of impurity of Salicylic (3 -4%), whereas customer requirement is a product with less than 0.5% Salicylic Acid. 2 Summary The present invention relates to a process of preparation of 2 Ethoxy Benzoic Acid comprising the steps of i) reacting Salicylic Acid with diethyl sulphate and a quaternary ammonium salt in the presence of an alkali hydroxide solution, ii) reacting the resultant with an alkali hydroxide solution and iii) reacting the resultant with mineral acid. Detailed Description of the Invention The present invention discloses the preparation of pure 2-Ethoxy Benzoic Acid devoid of Salicylic Acid impurity. The process involves three distinct steps: a) Etherification of phenolic OH group b) Esterification of carboxylic group c) Hydrolysis of ester group The process is initiated by reacting Salicylic Acid in aqueous alkaline solution (alkali hydroxide, R-OH) with Di Ethyl Sulphate at a pH of 10 to 11.5 in the presence of Benzyl chloride and Tri Ethyl Amine (TEA). The ether ester viz 2-Ethoxy Benzoic Acid Ethyl Ester thus formed is hydrolyzed in situ by addition of alkali hydroxide and heating the reaction mixture to 90°C-95°C. The resulting 2-Ethoxy Benzoic Acid Sodium Salt is treated with mineral acid to liberate 2-Ethoxy Benzoic Acid as oil. The oil is separated and washed with water. Traces of water are removed under vacuum at (40°C/0.5 mmHg). High vacuum distillation of the 3 product yields 2-Ethoxy Benzoic Acid (135 - 137°C/0.5 mmHg.) purity above 99.5 %. The following represents the chemical reactions involved in the synthesis of 2-Ethoxy Benzoic Acid. OOH JOH Water + (C2H5)2S04 + R-OH + TEA / Benzyl chloride 50 C Salicylic Acid Di Ethyl Sulphate alkali Hydroxide OOC2H5 ^C2H5 OC2H5 30%H2SO4 - COONa C2H5 Alkali Hydroxide 90 - 95 C 2-Ethoxy Benzoic Acid 2-Ethoxy Benzoic Acid Sodium Salt 2-Ethoxy Benzoic Acid Ethyl ester (Ether ester) The R-OH group can be selected from the group of Sodium hydroxide, Potassium hydroxide or Lithium hydroxide. Reaction of TEA and R-OH in the presence of benzyl chloride results in a quaternary ammonium salt. The quaternary ammonium salt is selected from either of tri ethyl benzyl ammonium chloride, Benzyl tributyl ammonium bromide, Benzyl tributyl 4 ammonium chloride, Benzyl trimethyl ammonium iodide, Benzyl trimethyl ammonium chloride, Benzyl triethyl ammonium bromide, Methyl tributyl ammonium chloride, Phenyl trimethyl ammonium chloride, Phenyl trimethyl ammonium iodide, Tetrabutyl ammonium chloride, Tetrabutyl ammonium fluoride or Tetrabutyl ammonium hydrogen sulphate. The present invention will now be described with reference to the following examples. However, the said examples in no way limit the present invention. Example 1 Charged Salicylic Acid (1.0 Kg) in water (1.2 Kg) and reacted with TEA (0.02 Kg) and Benzyl chloride (0.026 Kg) and Sodium hydroxide (0.580 Kg). This is followed by addition of Diethyl Sulfate (2.6 Kg) at a pH of 10 to 11.15. The contents were stirred at 50°C for 18 hours. During the stirring process the pH was maintained at 11 by adding caustic till Salicylic acid was below the detectable limit. When reaction was complete (Salicylic acid/ Ethyl salicylate undetectable) at 50°C, the contents were hydrolyzed by adding 0.3 Kg Sodium hydroxide and 0.3 Litre of water and heated at 95°C. Then contents were cooled to 30°C. The pH adjusted after acidification was 2.5 at 30°C. Then contents were further stirred for 1 hour and allowed to settle at 30°C. Lower layer was separated and the upper organic layer of 2-Ethxoy Benzoic Acid was washed with 1.0 Litre water to separate the aqueous layer. The crude 2-Ethoxy Benzoic acid was found to have a moisture content ~ 6.0 - 7.0% w/w which was dried under vacuum at 40°C-45°C at 5 0.5 mm Hg. This was followed by the vacuum distillation of the product at 135°C-138°C/1.0mmHg. Characteristics and the Yield of the product Distilled 2-Ethoxy Benzoic Acid = 1.0 Kg % Age yield main cut = 83.33% (Theory) GC purity >99.5% Salicylic Acid content: Nil Example 2 Charged Salicylic Acid (1.0 Kg) in water (1.2 Kg) and reacted with Tetra Butyl Ammonium Bromide (TBAB, 0.040 Kg) and Sodium hydroxide (0.580 Kg) followed by Diethyl Sulfate addition (2.6 Kg). The Diethyl Sulfate addition was done at a pH range of 10 to 11.15. The contents were stirred at 26°C -30°C for 12-18 hours. For pH adjustments, additional (0.100 Kg) Sodium Hydroxide may be required. When reaction is complete at room temperature (26°C 30°C), the contents were hydrolyzed by adding 0.3 Kg Sodium hydroxide and 0.3 Litre of water at 80°C -95°C. The contents are cooled to 30-40°C and acidified. The pH adjusted after acidification was found to be in the range of 2.5 to 3.0 at 30°C. Contents are stirred for 1 hour and allowed to settle at 30°C. Mother liquor from the lower layer was separated. Organic Layer of 2-Ethoxy Benzoic Acid was washed with 1.0 Litre of water and further the aqueous layer was separated. The 6 washing step was repeated twice and the crude 2-Ethoxy Benzoic Acid was collected. The crude 2-Ethoxy Benzoic acid has moisture content ~ 6.0 - 7.0% w/w which was dried under vacuum at 40°C-45°C at 0.5 mm Hg. As the moisture content of 2-Ethoxy Benzoic Acid at 40°C-50°C/0.5 mm Hg reached 0.06%, the main fraction of 2-Ethoxy Benzoic Acid was collected by distilling under vacuum (135°C -138°C/1 mm Hg). Characteristics and the Yield of the product Distilled 2-Ethoxy Benzoic Acid = 1.05 Kg. % Age yield main cut = 87.5%) (Theory) GC purity 99.5% Salicylic Acid content: Nil Example 3 Charge Salicylic Acid (1.0 Kg) in water (1.2 Kg) Charge Tetra Butyl Ammonium Hydrogen sulphate (0.040 Kg) Charge Sodium hydroxide (0.580 Kg) followed by Diethyl Sulfate addition. (2.6 Kg) The Diethyl Sulfate addition is made at pH 10 to 11.15. The contents are stirred at 26-30°C for 12-18 hours. For pH adjustment additional (0.100 Kg) Sodium Hydroxide will be required. When reaction is complete at room temperature (26-30°C), then the contents are hydrolyzed by adding 0.3 Kg Sodium hydroxide and 0.3 Litre of water at 80-95°C. Then cool the 7 contents to 30-40°C. The pH adjusted after acidification is 2.5 to 3.0 at 30°C. Then stir the contents for 1 hour. Then settle the contents at 30°C. Then separate mother liquor from the bottoms (lower layer) Wash the Organic Layer of 2-Ethoxy Benzoic Acid with (1.0 Litre) water and separate the aqueous layer. Again wash the organic layer of 2-Ethoxy Benzoic Acid with (1.0 Litre) water and separate the aqueous layer. Again wash the organic layer with water and collect 2-Ethoxy Benzoic Acid crude. The crude 2-Ethoxy Benzoic acid has moisture content ~ 6.0 - 7.0% w/w which is dried under vacuum at 40-45°C at 0.5 mm Hg. When moisture content of 2-Ethoxy Benzoic Acid at 40-50°C/0.5 mm Hg reached 0.06%. Then collect the main fraction of 2-Ethoxy Benzoic Acid by distilling under vacuum 135-138°C/1 mmHg. Distilled 2-Ethoxy Benzoic Acid = 1.0 Kg. % Age yield main cut = 83.33% (Theory) GC purity 99.12% Salicylic Acid content: Nil 8 We claim: 1. A process of preparation of 2-Ethoxy Benzoic Acid comprising the steps of i) reacting Salicylic Acid with diethyl sulphate and a quaternary ammonium salt in the presence of an alkali hydroxide solution, ii) reacting the resultant with an alkali hydroxide solution and iii) reacting the resultant with mineral acid. 2. A process of preparing 2-Ethoxy Benzoic Acid as claimed in Claim 1, wherein said quaternary ammonium salt is tri ethyl benzyl ammonium chloride, Benzyl tributyl ammonium bromide, Benzyl tributyl ammonium chloride, Benzyl trimethyl ammonium iodide, Benzyl trimethyl ammonium chloride, Benzyl triethyl ammonium bromide, Methyl tributyl ammonium chloride, Phenyl trimethyl ammonium chloride, Phenyl trimethyl ammonium iodide, Tetrabutyl ammonium chloride, Tetrabutyl ammonium fluoride or Tetrabutyl ammonium hydrogen sulphate. 3. A process of preparing 2-Ethoxy Benzoic Acid as claimed in Claim 1 wherein said quaternary ammonium salt is prepared in situ. 4. A process of preparing 2-Ethoxy Benzoic Acid as claimed in Claim 1, wherein said alkali hydroxide in step (i) is selected from sodium hydroxide, potassium hydroxide or lithium hydroxide. 9 5. A process of preparing 2-Ethoxy Benzoic Acid as claimed in Claim 1, wherein reaction at step (i) is maintained at pH between 10 to 11.5. 6. A process of preparation of preparing 2-Ethoxy Benzoic Acid as claimed in Claim 1, wherein step (i) is stirred at 25° C to 50° C for 12 to 18 hours. 7. A process of preparation of preparing 2-Ethoxy Benzoic Acid as claimed in Claim 1, wherein step (ii) is first heated to 90°C to 95° C, then cooled to 28°C to 30° C. 8. A process of preparing 2-Ethoxy Benzoic Acid as claimed in Claim 1, wherein Salicylic Acid/Ethyl Salicylate contents in distilled product are less than 0.5%. 9. A process of preparing 2-Ethoxy Benzoic Acid as herein described with reference to the examples accompanying the specification. 10 ABSTRACT The present invention relates to a process of preparation of 2 Ethoxy Benzoic Acid comprising the steps of i) reacting Salicylic Acid with diethyl sulphate and a quaternary ammonium salt in the presence of an alkali hydroxide solution, ii) reacting the resultant with an alkali hydroxide solution and iii) reacting the resultant with mineral acid. S-3/PATENT/GUJRAT ORGANICS/2-EBA_CS_FINAL_13042006 11

Full Text

FORM 2
THE PATENTS ACT, 1970
(39 OF 1970)
&
THE PATENT RULES, 2003
COMPLETE SPECIFICATION
[SECTION 10 AND RULE 13]
"A PROCESS TO MANUFACTURE 2-ETHOXY
BENZOIC ACID"

APPLICANT:

GUJARAT ORGANICS LIMITED

NATIONALITY: AN INDIAN COMPANY INCORPORATED UNDEF

ADDRESS:

THE COMPANIES ACT, 1956.
PLOT NO. 127/1, GIDC ESTATE, ANKLESHWAR

393 002, DIST.BHARUCH, GUJARAT STATE,
INDIA.
THE FOLLOWING SPECIFICATION PARTICULARLY DESCRIBES THE NATURE OF THIS INVENTION AND THE MANNER IN WHICH IT IS TO BE

PERFORMED:

Field of Invention
The present invention relates to a process of preparing 2-Ethoxy Benzoic Acid. The disclosure describes an economical method of preparing 2-Ethoxy Benzoic Acid free of Salicylic Acid impurity.
Background
In the prior art, 2-Ethoxy Benzoic Acid is prepared in two steps from Salicylamide. Firstly, Salicylamide in aqueous alkaline solution is reacted with Di Ethyl Sulphate to yield ether amide (2-Ethoxy Benzamide). As a second step, the said amide is hydrolyzed in situ by addition of alkali hydroxide and heating it. The resulting 2-Ethoxy Benzoic Acid sodium salt is treated with mineral acid to liberate 2-Ethoxy Benzoic Acid as oil. The oil is separated and washed with water. Traces of water in the product are removed as Ethylene Dichloride water azeotrope. Further, careful vacuum distillation of the product results in 2-Ethoxy Benzoic Acid (135°C-138°C / 0.5 mmHg) with Salicylic acid impurity of 3-4 %. 2-Ethoxy Benzoic Acid is cleaved to Salicylic Acid in the presence of moisture and acidity.
The drawbacks of prior art is that the raw material Salicylamide is obtained after three steps and overall yields are low (65%)., based on theory. The material has high level of impurity of Salicylic (3 -4%), whereas customer requirement is a product with less than 0.5% Salicylic Acid.
2

Summary
The present invention relates to a process of preparation of 2 Ethoxy Benzoic Acid comprising the steps of i) reacting Salicylic Acid with diethyl sulphate and a quaternary ammonium salt in the presence of an alkali hydroxide solution, ii) reacting the resultant with an alkali hydroxide solution and iii) reacting the resultant with mineral acid.
Detailed Description of the Invention
The present invention discloses the preparation of pure 2-Ethoxy Benzoic Acid devoid of Salicylic Acid impurity. The process involves three distinct steps:
a) Etherification of phenolic OH group
b) Esterification of carboxylic group
c) Hydrolysis of ester group
The process is initiated by reacting Salicylic Acid in aqueous alkaline solution (alkali hydroxide, R-OH) with Di Ethyl Sulphate at a pH of 10 to 11.5 in the presence of Benzyl chloride and Tri Ethyl Amine (TEA). The ether ester viz 2-Ethoxy Benzoic Acid Ethyl Ester thus formed is hydrolyzed in situ by addition of alkali hydroxide and heating the reaction mixture to 90°C-95°C. The resulting 2-Ethoxy Benzoic Acid Sodium Salt is treated with mineral acid to liberate 2-Ethoxy Benzoic Acid as oil. The oil is separated and washed with water. Traces of water are removed under vacuum at (40°C/0.5 mmHg). High vacuum distillation of the
3

product yields 2-Ethoxy Benzoic Acid (135 - 137°C/0.5 mmHg.) purity above 99.5 %.
The following represents the chemical reactions involved in the synthesis of 2-Ethoxy Benzoic Acid.

OOH
JOH

Water

+ (C2H5)2S04 + R-OH + TEA / Benzyl chloride

50 C

Salicylic Acid Di Ethyl Sulphate alkali Hydroxide

OOC2H5
^C2H5
OC2H5
30%H2SO4
-
COONa

C2H5
Alkali Hydroxide
90 - 95 C

2-Ethoxy Benzoic Acid 2-Ethoxy Benzoic Acid Sodium Salt 2-Ethoxy Benzoic Acid Ethyl ester
(Ether ester)
The R-OH group can be selected from the group of Sodium hydroxide, Potassium hydroxide or Lithium hydroxide. Reaction of TEA and R-OH in the presence of benzyl chloride results in a quaternary ammonium salt.
The quaternary ammonium salt is selected from either of tri ethyl benzyl ammonium chloride, Benzyl tributyl ammonium bromide, Benzyl tributyl
4

ammonium chloride, Benzyl trimethyl ammonium iodide, Benzyl trimethyl ammonium chloride, Benzyl triethyl ammonium bromide, Methyl tributyl ammonium chloride, Phenyl trimethyl ammonium chloride, Phenyl trimethyl ammonium iodide, Tetrabutyl ammonium chloride, Tetrabutyl ammonium fluoride or Tetrabutyl ammonium hydrogen sulphate.
The present invention will now be described with reference to the following examples. However, the said examples in no way limit the present invention.
Example 1
Charged Salicylic Acid (1.0 Kg) in water (1.2 Kg) and reacted with TEA (0.02 Kg) and Benzyl chloride (0.026 Kg) and Sodium hydroxide (0.580 Kg). This is followed by addition of Diethyl Sulfate (2.6 Kg) at a pH of 10 to 11.15. The contents were stirred at 50°C for 18 hours. During the stirring process the pH was maintained at 11 by adding caustic till Salicylic acid was below the detectable limit. When reaction was complete (Salicylic acid/ Ethyl salicylate undetectable) at 50°C, the contents were hydrolyzed by adding 0.3 Kg Sodium hydroxide and 0.3 Litre of water and heated at 95°C. Then contents were cooled to 30°C. The pH adjusted after acidification was 2.5 at 30°C. Then contents were further stirred for 1 hour and allowed to settle at 30°C. Lower layer was separated and the upper organic layer of 2-Ethxoy Benzoic Acid was washed with 1.0 Litre water to separate the aqueous layer. The crude 2-Ethoxy Benzoic acid was found to have a moisture content ~ 6.0 - 7.0% w/w which was dried under vacuum at 40°C-45°C at
5

0.5 mm Hg. This was followed by the vacuum distillation of the product at 135°C-138°C/1.0mmHg.
Characteristics and the Yield of the product
Distilled 2-Ethoxy Benzoic Acid = 1.0 Kg % Age yield main cut = 83.33% (Theory) GC purity >99.5% Salicylic Acid content: Nil
Example 2
Charged Salicylic Acid (1.0 Kg) in water (1.2 Kg) and reacted with Tetra Butyl Ammonium Bromide (TBAB, 0.040 Kg) and Sodium hydroxide (0.580 Kg) followed by Diethyl Sulfate addition (2.6 Kg). The Diethyl Sulfate addition was done at a pH range of 10 to 11.15. The contents were stirred at 26°C -30°C for 12-18 hours. For pH adjustments, additional (0.100 Kg) Sodium Hydroxide may be required. When reaction is complete at room temperature (26°C 30°C), the contents were hydrolyzed by adding 0.3 Kg Sodium hydroxide and 0.3 Litre of water at 80°C -95°C. The contents are cooled to 30-40°C and acidified. The pH adjusted after acidification was found to be in the range of 2.5 to 3.0 at 30°C. Contents are stirred for 1 hour and allowed to settle at 30°C. Mother liquor from the lower layer was separated. Organic Layer of 2-Ethoxy Benzoic Acid was washed with 1.0 Litre of water and further the aqueous layer was separated. The
6

washing step was repeated twice and the crude 2-Ethoxy Benzoic Acid was collected. The crude 2-Ethoxy Benzoic acid has moisture content ~ 6.0 - 7.0% w/w which was dried under vacuum at 40°C-45°C at 0.5 mm Hg.
As the moisture content of 2-Ethoxy Benzoic Acid at 40°C-50°C/0.5 mm Hg reached 0.06%, the main fraction of 2-Ethoxy Benzoic Acid was collected by distilling under vacuum (135°C -138°C/1 mm Hg).
Characteristics and the Yield of the product
Distilled 2-Ethoxy Benzoic Acid = 1.05 Kg. % Age yield main cut = 87.5%) (Theory)
GC purity 99.5%
Salicylic Acid content: Nil
Example 3
Charge Salicylic Acid (1.0 Kg) in water (1.2 Kg) Charge Tetra Butyl Ammonium Hydrogen sulphate (0.040 Kg) Charge Sodium hydroxide (0.580 Kg) followed by Diethyl Sulfate addition. (2.6 Kg) The Diethyl Sulfate addition is made at pH 10 to 11.15. The contents are stirred at 26-30°C for 12-18 hours. For pH adjustment additional (0.100 Kg) Sodium Hydroxide will be required. When reaction is complete at room temperature (26-30°C), then the contents are hydrolyzed by adding 0.3 Kg Sodium hydroxide and 0.3 Litre of water at 80-95°C. Then cool the
7

contents to 30-40°C. The pH adjusted after acidification is 2.5 to 3.0 at 30°C. Then stir the contents for 1 hour. Then settle the contents at 30°C. Then separate mother liquor from the bottoms (lower layer) Wash the Organic Layer of 2-Ethoxy Benzoic Acid with (1.0 Litre) water and separate the aqueous layer. Again wash the organic layer of 2-Ethoxy Benzoic Acid with (1.0 Litre) water and separate the aqueous layer. Again wash the organic layer with water and collect 2-Ethoxy Benzoic Acid crude. The crude 2-Ethoxy Benzoic acid has moisture content ~ 6.0 - 7.0% w/w which is dried under vacuum at 40-45°C at 0.5 mm Hg.
When moisture content of 2-Ethoxy Benzoic Acid at 40-50°C/0.5 mm Hg reached 0.06%. Then collect the main fraction of 2-Ethoxy Benzoic Acid by distilling under vacuum 135-138°C/1 mmHg.
Distilled 2-Ethoxy Benzoic Acid = 1.0 Kg. % Age yield main cut = 83.33% (Theory) GC purity 99.12% Salicylic Acid content: Nil
8

We claim:
1. A process of preparation of 2-Ethoxy Benzoic Acid comprising the steps of i) reacting Salicylic Acid with diethyl sulphate and a quaternary ammonium salt in the presence of an alkali hydroxide solution, ii) reacting the resultant with an alkali hydroxide solution and iii) reacting the resultant with mineral acid.
2. A process of preparing 2-Ethoxy Benzoic Acid as claimed in Claim 1, wherein said quaternary ammonium salt is tri ethyl benzyl ammonium chloride, Benzyl tributyl ammonium bromide, Benzyl tributyl ammonium chloride, Benzyl trimethyl ammonium iodide, Benzyl trimethyl ammonium chloride, Benzyl triethyl ammonium bromide, Methyl tributyl ammonium chloride, Phenyl trimethyl ammonium chloride, Phenyl trimethyl ammonium iodide, Tetrabutyl ammonium chloride, Tetrabutyl ammonium fluoride or Tetrabutyl ammonium hydrogen sulphate.
3. A process of preparing 2-Ethoxy Benzoic Acid as claimed in Claim 1 wherein said quaternary ammonium salt is prepared in situ.
4. A process of preparing 2-Ethoxy Benzoic Acid as claimed in Claim 1, wherein said alkali hydroxide in step (i) is selected from sodium hydroxide, potassium hydroxide or lithium hydroxide.
9

5. A process of preparing 2-Ethoxy Benzoic Acid as claimed in Claim 1, wherein reaction at step (i) is maintained at pH between 10 to 11.5.
6. A process of preparation of preparing 2-Ethoxy Benzoic Acid as claimed in Claim 1, wherein step (i) is stirred at 25° C to 50° C for 12 to 18 hours.
7. A process of preparation of preparing 2-Ethoxy Benzoic Acid as claimed in Claim 1, wherein step (ii) is first heated to 90°C to 95° C, then cooled to 28°C to 30° C.
8. A process of preparing 2-Ethoxy Benzoic Acid as claimed in Claim 1, wherein Salicylic Acid/Ethyl Salicylate contents in distilled product are less than 0.5%.
9. A process of preparing 2-Ethoxy Benzoic Acid as herein described with reference to the examples accompanying the specification.

10

ABSTRACT
The present invention relates to a process of preparation of 2 Ethoxy Benzoic Acid comprising the steps of i) reacting Salicylic Acid with diethyl sulphate and a quaternary ammonium salt in the presence of an alkali hydroxide solution, ii) reacting the resultant with an alkali hydroxide solution and iii) reacting the resultant with mineral acid.
S-3/PATENT/GUJRAT ORGANICS/2-EBA_CS_FINAL_13042006
11

Documents:

471-MUM-2005-ABSTRACT 13-4-2006.pdf

471-mum-2005-abstract.doc

471-mum-2005-abstract.pdf

471-MUM-2005-CLAIMS 13-4-2006.pdf

471-mum-2005-claims(granted)-(13-04-2006).doc

471-mum-2005-claims(granted)-(13-04-2006).pdf

471-mum-2005-claims.doc

471-mum-2005-claims.pdf

471-MUM-2005-CORRESPONDENCE 8-7-2008.pdf

471-mum-2005-correspondence(08-07-2008).pdf

471-mum-2005-correspondence(ipo)-(03-12-2008).pdf

471-mum-2005-correspondence-received-ver-130406.pdf

471-mum-2005-correspondence-received.pdf

471-mum-2005-description (complete).pdf

471-MUM-2005-DESCRIPTION(COMPLETE) 13-4-2006.pdf

471-MUM-2005-FORM 1 8-7-2008.pdf

471-mum-2005-form 1(15-04-2005).pdf

471-mum-2005-form 18(06-10-2006).pdf

471-mum-2005-form 2 13-4-2006.pdf

471-mum-2005-form 2(granted)-(13-04-2006).doc

471-mum-2005-form 2(granted)-(13-04-2006).pdf

471-MUM-2005-FORM 2(TITLE PAGE) 13-4-2006.pdf

471-MUM-2005-FORM 3 8-7-2008.pdf

471-mum-2005-form 3(15-04-02005).pdf

471-MUM-2005-FORM 5 13-4-2006.pdf

471-mum-2005-form 5(13-04-2006).pdf

471-mum-2005-form-1.pdf

471-mum-2005-form-2(drawings).doc

471-mum-2005-form-2.doc

471-mum-2005-form-2.pdf

471-mum-2005-form-26.pdf

471-mum-2005-form-3.pdf

471-mum-2005-form-5.pdf

471-mum-2005-other documents(15-04-2005).pdf

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Patent Number

225931

Indian Patent Application Number

471/MUM/2005

PG Journal Number

07/2009

Publication Date

13-Feb-2009

Grant Date

03-Dec-2008

Date of Filing

15-Apr-2005

Name of Patentee

GUJRAT ORGANICS LTD.

Applicant Address

PLOT NO.127/1, GIDC ESTATE. ANKLESHWAR 393 002

Inventors:

#	Inventor's Name	Inventor's Address
1	BHIKSHANDARKOVIL PARTHASARATHI CHANDRASEKHAR	11/84-B,BRINDABAN SOCIETY, THANE (W)400 601
2	PATHAK RAJESH KUMAR	PLOT NO.127/1,GIDC ESTATE.ANKLESHWAR 393 002

PCT International Classification Number

C07K11

PCT International Application Number

N/A

PCT International Filing date

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1			NA