1
S-3/PA TENT/GUJARAT ORGANIC/NEW PATENT_MAY06/PIPEB_PS
FORM 2
THE PATENTS ACT. 1970
{39 OF 1970)
&
THE PATENT RULES, 2003
PROVISIONAL SPECIFICATION [SECTION 10 AND RULE 13]
"PARA ISOPROPOXY ETHYL BENZOATE AND A PROCESS OF PREPARATION THEREOF"
APPLICANT: GUJRAT ORGANICS LIMITED
NATIONALITY: AN INDIAN COMPANY INCORPORATED UNDER THE COMPANIES
ACT, 1956.
ADDRESS: PLOT NO. 127/1, GIDC ESTATE, ANKLESHWAR 393 002,
DIST.BHARUCH, GUJARAT STATE, INDIA.
THE FOLLOWING SPECIFICATION DESCRIBES THE INVENTION: -

The Present invention relates to Para Iso Propoxy ethyl benzoate (PIPEB) and the
process of preparation thereof.
Para Iso Propoxy ethyl benzoate (PIPEB) is used as a catalyst in polypropylene manufacturing.
The present invention discloses the synthesis of p-lso Propoxy ethyl benzoate by esterification of p-Hydroxy benzoic acid with ethanol in the presence of sulphonic acids followed by the recovery of excess ethanol by distillation. The residual material is purified in water by neutralization using a base viz, sodium bicarbonate/ sodium carbonate / sodium hydroxide/ dilute solution of potassium hydroxide in water.
Etherification of Ethyl paraben is done with solvents viz N,N-Diethyl Formamide or N,N-Dimethyl Formamide or Methyl iso butyl ketone or Ortho Di Chloro Benzene by the reaction of Ethyl paraben with Isopropyl halides (Br.CI or I) and bases MOH as raw material, followed by recovery of the respective bromide or chloride or iodide and solvent recoveries by high vacuum distillation.
In a preferred embodiment, the process of esterification is carried out in the presence of an aryl sulphonic acid e.g. Para Toluene sulphonic acid. The process of esterification can also be carried out in the presence of an alkyl sulphonic acid e.g. Methane sulphonic acid. Hydrochloric acid can also be used as a catalyst in the process of esterification, polymer sulphonic acid e.g. Ion-exchange resins like Indion 850/Duolite 368 can also be used as catalyst in the process of esterification.
Dry Ethyl paraben obtained from the above process is etherified using halogenated isopropyl derivatives (CI Br&l) in presence of a base such as NaOH or KOH in a solvent viz O.D.C.B., Methyl isobutyl ketone and N, N-Dimethyl Formamide.
The present invention is now illustrated with the following examples. The examples are only illustrative and in no way limit the scope of invention:

X)OH

Example-1
Charge N, N-Dimethyl Formamide (1.9 kg). Charge Ethyl paraben (2.0 kg) followed by the
slow addition of sodium hydroxide (0.750 kg) Stir the content for 4 hrs.Then add Isopropyl bromide
to convert Ethyl paraben to p-lso Propoxy ethyl benzoate. Maintain the reaction at 40-80 °C to
complete the reaction. Monitor the progress of the reaction on TLC.After completion of the reaction
.filter the solid sodium bromide and collect the mother liquor containing N, N-Dimethyl Formamide
and p-lso Propoxy ethyl benzoate. Distil out the N,N-Dimethyl Formamide under vacuum at 100
°C/1.0 mmHg and recover N,N-Dimethyl Formamide (1.7 kg) . Add water to the residue.Seperate
the upper organic layer, wash the organic layer with 5% NaOH solution (200 ml). Then wash the
organic layer with water (200 ml). Distil the organic layer under vacuum at 130 °C/1mmHg.
Weight of p-lso Propoxy ethyl benzoate=2.1 kg.
Yield=84% (Theoretical)
G.C.Purity=99.4%
p-lso Propoxy benzoic acid=0.04%
Example-2
Charge N,N-Diethyl Formamide (1.9 kg). Charge Ethyl paraben (2.0 kg) followed by the slow addition of sodium hydroxide (0.750 kg).Stir the content for 4.0 hrs.Than add Isopropyl bromide to convert ethyl paraben to p-lso Propoxy ethyl benzoate. Maintain the reaction at 40-80 °C to complete the reaction. Monitor the progress of the reaction on TLC.After completion of the reaction filter the solid sodium bromide and collect the mother liquor containing N, N-Diethyl Formamide and p-lso Propoxy ethyl benzoate.
Distil out the N,N-Diethyl Formamide under vacuum at 100 °C/1.0 mmHg and recover N,N-Diethyl Formamide (1.7 kg approximately) Add water to the residue.Seperate the upper organic layer, wash the organic layer with 5% NaOH solution (200 ml). Then wash the organic layer with water (200 ml) Distil the organic layer under vacuum at 130 °C/1mmHg.
Weight of p-lso Propoxy ethyl benzoate=2.2 kg.
Yield=88% (Theoretical)
G.C.Purity=99.4%
p-lso Propoxy benzoic acid=0.06%

5 Example-3
Charge N,N-Diethyl Formamide (1.9 kg) Charge Ethyl paraben (2.0 kg) followed by the
slow addition of potassium hydroxide (1.05 kg).Stir the content for 4.0 hrs.Then add Isopropyl
iodide to convert ethyl paraben to p-lso Propoxy ethyl benzoate. Maintain the reaction at 40-80 °C
to complete the reaction. Monitor the progress of the reaction on TLC.After completion of the
reaction filter the solid Potassium iodide and collect the mother liquor containing N, N-Diethyl
Formamide and p-lso Propoxy ethyl benzoate. Distil out the N,N-Diethyl Formamide under
vacuum at 100 °C/1.0 mmHg and recover N,N-Diethyl Formamide (1.7 kg approximately) Then
add water to the residue.Seperate the upper organic layer & wash the organic layer with 5%
NaOH / 5 % KOH / Soda ash / sodium bicarbonate solution (200 ml). Then wash the organic layer
with water (200 ml).Then distil out the organic layer under vacuum at 130 °C/1mmHg.
Weight of p-lso Propoxy ethyl benzoate=2.25 kg.
Yield=90% (Theoretical)
G.C.Purity=99.4%
p-lso Propoxy benzoic acid=0.05%
Example-4
Charge N,N-Diethyl Formamide (1.9 kg), Charge Ethyl paraben (2.0 kg) followed by the
slow addition of sodium hydroxide (0.750 kg).Stir the content for 4.0 hrs.Than add Isopropyl chloride to convert ethyl paraben to p-lso Propoxy ethyl benzoate. Maintain the reaction at 40-80 °C to complete the reaction. Monitor the progress of the reaction on TLC.After completion of the reaction filter the solid sodium chloride and collect the mother liquor containing N, N-Diethyl Formamide and p-lso Propoxy ethyl benzoate. Distil out the N,N-Diethyl Formamide under vacuum at 100 °C/1.0 mmHg and recover N,N-Diethyl Formamide (1.7 kg approximately) . Add water to the residue.Seperate the upper organic layer& wash the organic iayer with 5% NaOH solution (200 ml). Then wash the organic layer with water (200 ml).Then distil the organic layer under vacuum at 130 °C/1mmHg.
Weight of p-lso Propoxy ethyl benzoate=2.25 kg.
Yield=90% (Theoretical)
G.C.Purity=99.5%
p-lso Propoxy benzoic acid=0.04%

6 Example-5
Charge N,N-Diethyl Formamide (1.9 kg) Charge Ethyl paraben (2.0 kg) followed by the
slow addition of Potassium hydroxide (1.05 kg).Stir the content for 4.0 hrs.Than add Isopropyl
bromide to convert ethyl paraben to p-lso Propoxy ethyl benzoate. Maintain the reaction at 40-80
°C to complete the reaction. Monitor the progress of the reaction on TLC.After completion of the
reaction filter the solid Potassium bromide and collect the mother liquor containing N, N-Diethyl
Formamide and p-lso Propoxy ethyl benzoate. Distil out the N,N-Diethyl Formamide under
vacuum at 100 °C/1.0 mmHg and recover N,N-Diethyl Formamide (1.7 kg approximately). Add
water to the residue.Seperate the upper organic layer & wash the organic layer with 5% NaOH
solution (200 ml) Then wash the organic layer with water (200 ml).Then distil
the organic layer under vacuum at 130 °C/1mmHg.
Weight of p-lso Propoxy ethyl benzoate=2.325 kg.
Yield=93.0% (Theoretical)
G.C.Purity=99.5%
p-lso Propoxy benzoic acid=0.04%
Example-6
Charge Ortho Dichloro Benzene (1.9 kg), Charge Ethyl paraben (2.0 kg) followed by the slow addition of Potassium hydroxide (1.05 kg).Stir the content for 4.0 hrs.Then add Isopropyl bromide to convert ethyl paraben to p-lso Propoxy ethyl benzoate. Maintain the reaction at 40-80 °C to complete the reaction. Monitor the progress of the reaction on TLC.After completion of the reaction filter the solid Potassium bromide and collect the mother liquor containing Ortho Dichloro Benzene and p-lso Propoxy ethyl benzoate. Distil out the Ortho Dichloro Benzene under vacuum at 100 °C/1.0 mmHg and recover Ortho Dichloro Benzene (1.7 kg approximately) Then add water to the residue.Seperate the upper organic layer wash the organic layer with 5% NaOH solution (200 ml) Then wash the organic layer with water (200 ml).Then distil the organic layer under vacuum at 130 °C/1mmHg.
Weight of p-lso Propoxy ethyl benzoate=2.325 kg.
Yield=93.0% (Theoretical)
G.C.Purity=99.5%
p-lso Propoxy benzoic acid=0.04%

7 Example-7
Charge Methyl Isobutyl ketone (1.9 kg) Charge Ethyl paraben (2.0 kg) followed by the slow
addition of Potassium hydroxide (1.05 kg).Stir the content for 4.0 hrs.Then add Isopropyl bromide
to convert ethyl paraben to p-lso Propoxy ethyl benzoate. Maintain the reaction at 40-80 °C to
complete the reaction. Monitor the progress of the reaction on TLC.After completion of the reaction
filter the solid Potassium bromide and collect the mother liquor containing Methyl Isobutyl ketone
and p-lso Propoxy ethyl benzoate. Distil out the Methyl Isobutyl ketone under vacuum at 50°C/1.0
mmHg and recover Methyl Isobutyl ketone (1.7 kg approximately). Then add water to the
residue..Seperate the upper organic & layer wash the organic layer with 5% NaOH solution (200
ml) Then wash the organic layer with water (200 ml).Than distil
the organic layer under vacuum at 130 °C/1mmHg.
Weight of p-lso Propoxy ethyl benzoate=2.325 kg.
Yield=93.0% (Theoretical)
G.C.Purity=99.5%
p-lso Propoxy benzoic acid=0.04%
Advantages:-
1) The present invention synthesizes a new product p-lso Propoxy ethyl benzoate with very low p-Iso Propoxy benzoic acid impurity (less than 0.1%).
2) The present invention synthesizes p-lso Propoxy ethyl benzoate of 99.4% to 99.5%.G.C.Purity.
3) The moisture content of p-lso Propoxy ethyl benzoate is 100 to 500 parts per million (ppm).
4) The present invention is an economical and commercial method of producing the new product p-lso Propoxy ethyl benzoate.

Dated this 9th day of May 2006.

To:
The Controller of Patents, The Patent Office, Mumbai 400 037.