FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION
(See section 10 and rule 13)
1. Title of the Invention
A PROCESS FOR THE SYNTHESIS OF QUATERNARY AMMONIUM COMPOUNDS
2. Applicant(s)
Name Nationality Address
GHARDA CHEMICALS LIMITED Indian R & D CENTER, B-27, MIDC PHASE-I, DOMBIVILI (E), DIST.THANE-421203, MAHARASHTRA, INDIA
3. Preamble to the description
The following specification particularly describes the invention and the manner in which it is to be performed

FIELD
The present disclosure relates to a process for the synthesis of quaternary ammonium compounds.
BACKGROUND
The background information herein below relates to the present disclosure but is not necessarily prior art.
The use of quaternary ammonium compounds as antiseptics and disinfectants is well known in the art. Many quaternary ammonium compounds have been synthesized that are not only antibacterial, but also possess antifungal and antiviral capabilities. Coating of quaternary ammonium moieties onto various surfaces represents one of the most promising strategies for the preparation of antimicrobial materials.
However, the widespread and injudicious use of antibiotics and disinfectants has induced the emergence of new strains of antimicrobial-resistant microorganisms, leading to dramatically increased difficulties in the antimicrobial issue. With the unceasing emergence of new strains of global infectious pathogens in recent years, there is an urgent demand for exploring more efficient, broad-spectrum and long-lasting antimicrobial agents.
Therefore, there felt a need to provide a process for the synthesis of quaternary ammonium compounds that mitigates the drawbacks mentioned herein above.
OBJECTS
Some of the objects of the present disclosure, which at least one embodiment herein satisfies, are as follows:

An object of the present disclosure is to ameliorate one or more problems of the prior art or to at least provide a useful alternative.
Another object of the present disclosure is to provide a process for the synthesis of quaternary ammonium compounds that are useful as antiviral and antimicrobial agent.
Yet another object of the present disclosure is to provide a process for the synthesis of quaternary ammonium compounds that can be easily coated on different surfaces to impart protection from viruses.
Still another object of the present disclosure is to provide a process for the synthesis of quaternary ammonium compounds that possess comparatively high level of antimicrobial activity against a broad spectrum of microorganisms including viruses.
Another object of the present disclosure is to provide a process for the synthesis of quaternary ammonium compounds that are cost effective.
Other objects and advantages of the present disclosure will be more apparent from the following description, which is not intended to limit the scope of the present disclosure.
SUMMARY
The present disclosure relates to a process for the synthesis of a quaternary
ammonium compound. The process comprises the step of reacting 4-((6-
bromohexyl)oxy)phenyl)(phenyl)methanone with dimethylamine in a first fluid
medium at a first predetermined temperature for a first predetermined time period
to obtain 4-((6-(dimethylamino)hexyl)oxyphenyl)(phenyl) methanone. Separately,
bromoacetyl bromide is reacted with decyl amine by using a base in a second fluid
medium at a second predetermined temperature for a second predetermined time
period to obtain 2-bromo-N-decyl acetamide. 4-((6-

(dimethylamino)hexyl)oxyphenyl (phenyl)methanone so obtained is reacted with 2-bromo-N-decyl acetamide in a third fluid medium at a third predetermined temperature for a third predetermined time period to obtain the quaternary ammonium compound.
DETAILED DESCRIPTION
Embodiments are provided so as to thoroughly and fully convey the scope of the present disclosure to the person skilled in the art. Numerous details are set forth, relating to specific components, and methods, to provide a complete understanding of embodiments of the present disclosure. It will be apparent to the person skilled in the art that the details provided in the embodiments should not be construed to limit the scope of the present disclosure. In some embodiments, well-known processes, well-known apparatus structures, and well-known techniques are not described in detail.
The terminology used, in the present disclosure, is only for the purpose of explaining a particular embodiment and such terminology shall not be considered to limit the scope of the present disclosure. As used in the present disclosure, the forms "a,” "an," and "the" may be intended to include the plural forms as well, unless the context clearly suggests otherwise. The terms "comprises," "comprising," “including,” and “having,” are open ended transitional phrases and therefore specify the presence of stated features, integers, steps, operations, elements, modules, units and/or components, but do not forbid the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. The particular order of steps disclosed in the method and process of the present disclosure is not to be construed as necessarily requiring their performance as described or illustrated. It is also to be understood that additional or alternative steps may be employed.

As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed elements.
The terms first, second, third, etc., should not be construed to limit the scope of the present disclosure as the aforementioned terms may be only used to distinguish one element, component, region, layer or section from another component, region, layer or section. Terms such as first, second, third etc., when used herein do not imply a specific sequence or order unless clearly suggested by the present disclosure.
Use of antibiotics and disinfectants has induced the emergence of new strains of antimicrobial-resistant microorganisms, leading to dramatically increased difficulties in the antimicrobial issue. With the unceasing emergence of new strains of global infectious pathogens in recent years there is an urgent demand for exploring more efficient, broad-spectrum and long-lasting antimicrobial agents. Quaternary ammonium compounds can also act as an antimicrobial agent, however, the existing process for the preparation of the same have drawbacks.
The present disclosure provides a process for synthesis of quaternary ammonium compounds that possess antimicrobial activity and antiviral activity.
The process for the synthesis of a quaternary ammonium compound comprises the following steps:
(i) reacting 4-((6-bromohexyl)oxy)phenyl)(phenyl)methanone with
dimethylamine in a first fluid medium at a first predetermined temperature
for a first predetermined time period to obtain 4-((6-
(dimethylamino)hexyl)oxyphenyl)(phenyl) methanone:
(ii) separately reacting bromoacetyl bromide with decyl amine by using a base in a second fluid medium at a second predetermined temperature for a

second predetermined time period to obtain 2-bromo-N-decyl acetamide; and
(iii) reacting 4-((6-(dimethylamino)hexyl)oxyphenyl (phenyl)methanone formed in step (i) with 2-bromo-N-decyl acetamide formed in step (ii) in a third fluid medium at a third predetermined temperature for a third predetermined time period to obtain the quaternary ammonium compound.
The process for the synthesis of a quaternary ammonium compound is described in detail as given below:
Step 1: Synthesis of 4-((6-(dimethylamino)hexyl)oxyphenyl
(phenyl)methanone (Compound A):
In the first step 4-((6-bromohexyl)oxy)phenyl)(phenyl)methanone is reacted with
dimethylamine in a first fluid medium at a first predetermined temperature for a
first predetermined time period to obtain 4-((6-
(dimethylamino)hexyl)oxyphenyl)(phenyl) methanone (Compound A).
The schematic representation of the synthesis of 4-((6-
(dimethylamino)hexyl)oxyphenyl (phenyl)methanone (Compound A) is given in Scheme 1 below:


In accordance with the embodiments of the present disclosure, a mixture of at least one first fluid medium and crude 4-((6-bromohexyl)oxy)phenyl)(phenyl) methanone are charged in a pressure reactor to obtain a mixture. A gas of dimethyl amine is passed to the mixture in the reactor under pressure followed by heating at a first predetermined temperature for a first predetermined time period to obtain 4-((6-(dimethylamino)hexyl)oxyphenyl)(phenyl) methanone (Compound A).
In accordance with the embodiments of the present disclosure, the first fluid medium is selected from hexane and chloroform. In an exemplary embodiment, the first fluid medium is hexane.
In accordance with the present disclosure, the first predetermined temperature is in the range of 40°C to 70°C. In an exemplary embodiment, the first predetermined temperature is 60°C.

In accordance with the present disclosure, the first predetermined time period is in the range of 10 to 15 hours. In an exemplary embodiment, the first predetermined time period is 12 hours.
In accordance with the embodiments of the present disclosure, the reactant 4-((6-bromohexyl)oxy)phenyl)(phenyl)methanone is prepared by reacting 4-hydroxy benzophenone with 1,6-dibromohexane by using a base in a fluid medium at a temperature in the range of 20°C to 40°C for a time period in the range of 2 to 20 hours to obtain crude 4-((6-bromohexyl)oxy)phenyl(phenyl) methanone as described in scheme 1A.

In accordance with the embodiment of the present disclosure, a mixture of 4-hydroxy benzophenone, 1,6-dibromohexane, a base and fluid medium is stirred under nitrogen atmosphere at a temperature in the range of 20°C to 40°C for a time period in the range of 2 to 20 hours to obtain a reaction mixture. The reaction mixture is cooled to a temperature range of 5°C to 25°C and after workup crude 4-((6-bromohexyl)oxy)phenyl(phenyl) methanone is obtained. The crude 4-((6-bromohexyl)oxy)phenyl(phenyl) methanone have HPLC purity of 95% and dimer impurity, 1,6-Bis(4-benzoylphenoxy)hexane less than 3.0%.
In accordance with the embodiment of the present disclosure, the base is selected from potassium carbonate, sodium carbonate, lithium carbonate and cesium carbonate. In an exemplary embodiment, the base is potassium carbonate.

In accordance with the embodiment of the present disclosure, the fluid medium is selected from dimethyl formamide (DMF), dimethyl sulfoxide (DMSO), dimethylacetamide (DMAc), N-methyl-2-pyrrolidone (NMP) and acetonitrile (ACN). In an exemplary embodiment, the fluid medium is dimethyl formamide.
In accordance with the embodiment of the present disclosure, a molar ratio of 4-hydroxy benzophenone to 1,6-dibromohexane is in the range of 1:1.5 to 1:10. In an exemplary embodiment of the present disclosure, the molar ratio of 4-hydroxy benzophenone to 1,6-dibromohexane is 1:3.
Step 2: Synthesis of 2-bromo-N-decyl acetamide (Compound B):
Separately, bromoacetyl bromide is reacted with decyl amine in a second fluid medium and a base at a second predetermined temperature for a second predetermined time period to obtain 2-bromo-N-decyl acetamide (Compound B).
The schematic representation of the synthesis of 2-bromo-N-decyl acetamide (Compound B) is given in Scheme 2 below:

In accordance with the embodiments of the present disclosure, bromoacetyl bromide is added in a second fluid medium to obtain a reaction mass. The reaction mass is cooled to a second predetermined temperature. To the cooled reaction mass, a mixture of second fluid medium, a base and decyl amine is added to obtain slurry. The slurry is maintained at second predetermined temperature for a second predetermined time period to obtain 2-bromo-N-decyl acetamide.

In accordance with the embodiments of the present disclosure, the second fluid medium is selected from dichloromethane (MDC) and ethylenedichloride (EDC). In an exemplary embodiment, the second fluid medium is dichloromethane.
In accordance with the embodiments of the present disclosure, the base is selected from triethylamine (TEA), picoline and pyridine. In an exemplary embodiment, the base is trimethylamine.
In accordance with the present disclosure, the second predetermined temperature is in the range of -5°C to 10°C. In an exemplary embodiment, the second predetermined temperature is 0°C.
In accordance with the present disclosure, the second predetermined time period is in the range of 0.5 hour to 2 hours. In an exemplary embodiment, the second predetermined time period is 1 hour.
In accordance with the embodiments of the present disclosure, the reactant bromoacetyl bromide is prepared by adding bromine in a mixture of acetic acid and red phosphorous at a temperature in the range of 10°C to 30°C for a time period in the range of 2 to 8 hours to obtain a reaction mass. The gases formed during the reaction are scrubbed in water. The reaction mass is heated to a temperature range in the range of 50°C to 75°C and bromine is added over a time period in the range of 3 to 5 hours to obtain slurry. The slurry is further heated to a temperature in the range of 90°C to 110°C for a time period in the range of 1 to 3 hours followed by cooling to a temperature in the range of 20°C to 40°C and worked up to get product, bromoacetylbromide, having purity greater than 97%.
In accordance with the embodiments of the present disclosure, the preparation of reactant decylamine involves following steps:

a) phthalic anhydride is heated to a temperature in the range of 150°C to 250°C and ammonia gas is passed over a period of 4 to 8 hours to obtain phthalimide;
b) a reaction mixture of phthalimide obtained in step a), N-decyl bromide, potassium carbonate and dimethylformamide is heated at a temperature in the range of 100°C to 140°C under nitrogen atmosphere for about time period in the range of 2 to 6 hours to obtain N-decyl phthalimide after work up;
c) a mixture of N-decyl phthalimide obtained in step b), methanol and hydrazine hydrate is heated at a temperature in the range of 60 °C to 70 °C for a time period in the range of 2 to 5 hours to obtain a reaction mass. Water is added to the mass and distilled at 90°C to 95°C, cooled to 65°C to 75°C followed by adding hydrochloric acid to the reaction mass, followed by heating at a temperature in the range of 80 °C to 110 °C for the period of 1.5 to 2.5 hours to obtain a product mixture. The product mixture is cooled and filtered followed by neutralizing the filtrate using sodium hydroxide and worked up to give decylamine.
Step 3: Synthesis of Quaternary ammonium compound, 6-(4-
benzoylphenoxy)-N-(2-(decylamino)-2-oxoethyl)-N,N-dimethylhexan-1-ammonium bromide (Compound C):
4-((6-(dimethylamino)hexyl)oxyphenyl (phenyl)methanone (Compound A) formed in step 1 is reacted with 2-bromo-N-decyl acetamide (Compound B) formed in step 2 in a third fluid medium at a third predetermined temperature for a third predetermined time period to obtain the quaternary ammonium compound, 6-(4-benzoylphenoxy)-N-(2-(decylamino)-2-oxoethyl)-N,N-dimethylhexan-1-ammonium bromide (Compound C).

The schematic representation of the synthesis of 6-(4-benzoylphenoxy)-N-(2-(decylamino)-2-oxoethyl)-N,N-dimethylhexan-1-ammonium bromide (Compound C) is given in Scheme 3 below:

In accordance with the embodiments of the present disclosure, 4-((6-(dimethylamino)hexyl)oxy)phenyl)(phenyl)methanone (compound A) formed in step 1 and 2-bromo-N-decyl acetamide (compound B) formed in step 2 are added in a third fluid medium, under nitrogen atmosphere, under stirring to obtain a clear reaction mass. The reaction mass is heated at a third predetermined temperature for a third predetermined time period to form the quaternary ammonium compound, 6-(4-benzoylphenoxy)-N-(2-(decylamino)-2-oxoethyl)-N,N-dimethylhexan-1-ammonium bromide (Compound C).

In accordance with the embodiments of the present disclosure, the third fluid medium is selected from ethanol, methanol, propanol, butanol and ethyl acetate. In an exemplary embodiment, the third fluid medium is ethanol.
In accordance with the present disclosure, the third predetermined temperature is in the range of 35°C to 50°C. In an exemplary embodiment, the third predetermined temperature is 45°C.
In accordance with the present disclosure, the third predetermined time period is in the range of 10 to 20 hours. In an exemplary embodiment, the third predetermined time period is 16 hours.
In accordance with the embodiments of the present disclosure, a molar ratio of 4-((6-(dimethylamino)hexyl)oxyphenyl (phenyl)methanone to 2-bromo-N-decyl acetamide is in the range of 1:1.05 to 1:1.5. In an exemplary embodiment of the present disclosure, the molar ratio of 4-((6-(dimethylamino)hexyl)oxyphenyl (phenyl)methanone to 2-bromo-N-decyl acetamide is 1:1.2.
In accordance with the embodiments of the present disclosure, quaternary ammonium compound has a purity greater than 98% and a yield in the range of 75 to 95%.
In accordance with the embodiments of the present disclosure, the quaternary ammonium compound can be covalently coated onto different surfaces such as cotton, polyurethane, polyvinyl chloride, polypropylene, polystyrene, and the like. The surfaces coated with the quaternary ammonium compound are highly efficient against different kinds of drug resistance bacteria, fungi, and viruses.
In an embodiment, the quaternary ammonium compound (antiviral agent) is used with other adjuvants in personal protective equipments (PPE) for example face masks, face shield, gloves, and the like. by covalently coating onto different

surfaces such as cotton, polyurethane, polyvinyl chloride, polypropylene, polystyrene, and the like.
The foregoing description of the embodiments has been provided for purposes of illustration and not intended to limit the scope of the present disclosure. Individual components of a particular embodiment are generally not limited to that particular embodiment, but, are interchangeable. Such variations are not to be regarded as a departure from the present disclosure, and all such modifications are considered to be within the scope of the present disclosure.
EXPERIMENTAL DETAILS:
Experiment 1: Synthesis of Quaternary ammonium compound in accordance with the present disclosure
Step (i): Synthesis of 4-((6-(dimethylamino)hexyl)oxyphenyl
(phenyl)methanone
a) Synthesis of (4-((6-bromohexyl)oxy)phenyl)(phenyl)methanone
4-Hydroxy benzophenone (1 mole), 1,6-dibromohexane (3 moles/moles (m/m)),
potassium carbonate (1.5 m/m) and dry dimethylformamide (DMF) (1000 ml/m)
were taken in a reactor and stirred at 25 °C under nitrogen atmosphere for 18
hours to obtain a reaction mixture. The reaction was monitored by HPLC for the
absence of starting material i.e., 4-hydroxybenzophenone. Once the reaction was
completed, the reaction mixture was cooled to 10 °C followed by filtering to
remove inorganics along with major dimer impurity, 1,6-Bis(4-
benzoylphenoxy)hexane to obtain a clear filtrate and a residue.
The clear filtrate was poured into ice-water and extracted with ethylenedichloride (EDC) (2 extracts). The ethylenedichloride (EDC) was separated and combined. The ethylenedichloride (EDC) layer contained the product. The ethylenedichloride (EDC) was washed with 250 ml water to remove DMF, if any. The

ethylenedichloride (EDC) after water washing was concentrated to obtain a crude mass of product ((4-((6-bromohexyl)oxy)phenyl)(phenyl)methanone).
The crude product was filtered, washed with cold hexane and dried. The crude product was 70 % with HPLC purity greater than 95 % and impurity (dimer) < 3.0 %.
b) 4-((6-(dimethylamino)hexyl)oxyphenyl (phenyl)methanone
1 liter/Mole hexane and 4-((6-bromohexyl)oxy)phenyl(phenyl) methanone compound having >95% purity along with dimer impurity obtained in step a) were charged into a pressure reactor and 10 M/M dimethyl amine gas was passed into reactor under pressure of 3 kg/cm2 to obtain a mass. The mass was heated to 60°C and maintained at a pressure of 2 Kg/cm2 for 12 hr (reactor pressure of 3 Kg/cm2 was dropped to 2 Kg/cm2 during this step) to obtain a product mass. The reaction was monitored by HPLC for the absence of starting compound. Once the reaction was completed, and when HPLC showed absence of starting compound, the product mass was taken for work up.
The product mass was cooled to 25°C, released all DMA pressure. The product
mass was removed from reactor and filtered to separate an insoluble content and a
hexane filtrate. The Hexane filtrate was washed with water and was concentrated
completely to get the product 4-((6-(dimethylamino)hexyl)oxyphenyl
(phenyl)methanone. Average yield = (90%). Purity of the product >99% Dimer = <0.1%.
Step (ii): Synthesis of 2-bromo-N-decyl acetamide
A. Preparation of bromoacetyl bromide
Acetic acid (1 M), and Red phosphorous 0.337 m/m at 35°C, was charged in a reactor to form slurry. The slurry was cooled to 15°C to obtain a cooled slurry. 1st lot of bromine (1m/m) was added over a time period of 6 hours at 20°C in the

cooled slurry and the gases formed were scrubbed in water and estimated the HBr by addition of alkali (NaOH) to obtain a first reaction mass. The first reaction mass was heated to 60°C and further, 2nd lot of bromine was added (0.83m/m) at 60°C in 4 hours to obtain a second reaction mass. Further, the second reaction mass was heated to 100°C and maintained at 100°C for 2 hours to obtain a product mixture. After two hours the product mixture was cooled to 30°C to obtain two separate layers. Top layer was separated and was subjected for distillation to obtain bromo acetyl bromide (Classical purity: 97.2% bromo acetyl bromide and 2% Dibromo acetyl bromide).
B. Preparation of decylamine
Part-I: Phthalimide preparation
1 mole phthalic anhydride (147 g) was charged in a reactor and heated to 180°C and ammonia gas was passed for 1.3m/m at 240°C over a period of 6 hours to obtain a product mass comprising phthalimide. The reaction was monitored by HPLC for the absence of starting material. (Yield = 94% Purity = 99.7%). The product mass comprising phthalimide was taken for the next step without any further purification.
Part-II: N-decyl Phthalimide preparation
N-decyl bromide (221 g) (1 M), product mass comprising phthalimide (159 g, 1.08 m/m), K2CO3 86 g (0.62m/m) and DMF 800 ml/m were charged in a reactor to obtain a mixture. The mixture was heated to 120°C under nitrogen to obtain a reaction mass. The reaction mass was maintained at 120°C for 4 hours to obtain a resultant mass. After 4 hours the resultant mass was cooled to 15°C and filtered to obtain the product N-decyl phthalimide (yield: 90%; purity: 98%).
Part-III: Decyl amine preparation

N-decyl Phthalimide 287 g (1m), methanol (2240 ml/m) and hydrazine hydrate (78.96% pure, 99.4 g, 1.57m/m) were charged into a reactor to obtain a mixture. The mixture was heated at 75°C for 3 hours to obtain a reaction mass. 450 ml/m water was added to the reaction mass and the mixture of water and methanol was distilled till 95°C (1889 ml/m) followed by cooling to 70°C. Reaction mixture was acidified removed insoluble by filtration and the crude decyl amine was distilled under vacuum to obtain a pure decyl amine (yield 70% and purity 98%).
C. Preparation of 2-bromo-N-decyl acetamide
Dichloromethane (MDC) (1000 ml/m) and bromo acetyl bromide (1.05 m/m = 212 g) were charged in a reactor and was cooled at 0°C to obtain a mass. A mixture of MDC (1000ml/m), decyl amine (1m = 157 g) and TEA (1.m/m = 101 g) was added to the mass over a period of 3 hours at 0°C to obtain a reaction mixture. The reaction mixture was taken for work up to obtain 2-bromo-N-decyl acetamide (wt. = 255.26 g/m Yield = 92 m %) showing GC 95.06% 2-bromo-N-decyl acetamide.
Step (iii): Synthesis of Quaternary ammonium compound, 6-(4-benzoylphenoxy)-N-(2-(decylamino)-2-oxoethyl)-N,N-dimethylhexan-1-ammonium bromide
2.7 lit/Mole of absolute ethanol was taken into a reactor; and 1.0 M/M 4-[[6-(dimethylamino)-hexyl] oxy] phenyl (phenyl)methanone and 1.2 M/M 2-Bromo-N-Decyl acetamide were charged into the reactor under nitrogen atmosphere under stirring to obtain a reaction mixture. The reaction mixture was a light brown colored clear solution. The reaction mixture (light brown colored clear solution) was heated to 45°C under stirring for 16 hours to obtain a reaction mass. The reaction was monitored by HPLC. After 16 hours of stirring, the reaction mass was taken up for work up to isolate the product. Average weight of Crop = 475

gm/Mole. HPLC showed (4-[[6-(dimethylamino)-hexyl] oxy] phenyl : <1%; 2-Bromo-N-Decyl Acetamide : <0.10%; Final product: 99%).
TECHNICAL ADVANCEMENTS
The present disclosure described herein above has several technical advantages including, but not limited to, the realization of,
- a quaternary ammonium compound obtained by the process of the present disclosure, is cost effective and non-toxic to mammals; and
- a simple process for the synthesis of a quaternary ammonium compound.
Throughout this specification the word “comprise”, or variations such as “comprises” or “comprising, will be understood to imply the inclusion of a stated element, integer or step,” or group of elements, integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps.
The use of the expression “at least” or “at least one” suggests the use of one or more elements or ingredients or quantities, as the use may be in the embodiment of the invention to achieve one or more of the desired objects or results. While certain embodiments of the inventions have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the inventions. Variations or modifications to the formulation of this invention, within the scope of the invention, may occur to those skilled in the art upon reviewing the disclosure herein. Such variations or modifications are well within the spirit of this invention.
The numerical values given for various physical parameters, dimensions and quantities are only approximate values and it is envisaged that the values higher than the numerical value assigned to the physical parameters, dimensions and

quantities fall within the scope of the invention unless there is a statement in the specification to the contrary.
While considerable emphasis has been placed herein on the specific features of the preferred embodiment, it will be appreciated that many additional features can be added and that many changes can be made in the preferred embodiment without departing from the principles of the disclosure. These and other changes in the preferred embodiment of the disclosure will be apparent to those skilled in the art from the disclosure herein, whereby it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the disclosure and not as a limitation.

WE CLAIM:
1. A process for the synthesis of a quaternary ammonium compound, said
process comprising the following steps:
(iv) reacting 4-((6-bromohexyl)oxy)phenyl)(phenyl)methanone with dimethylamine in a first fluid medium at a first predetermined temperature for a first predetermined time period to obtain 4-((6-(dimethylamino)hexyl)oxyphenyl)(phenyl) methanone:
(v) separately reacting bromoacetyl bromide with decyl amine by using a base in a second fluid medium at a second predetermined temperature for a second predetermined time period to obtain 2-bromo-N-decyl acetamide; and
(vi) reacting 4-((6-(dimethylamino)hexyl)oxyphenyl
(phenyl)methanone formed in step (i) with 2-bromo-N-decyl acetamide formed in step (ii) in a third fluid medium at a third predetermined temperature for a third predetermined time period to obtain the quaternary ammonium compound.
2. The process as claimed in claim 1, wherein 4-((6-bromohexyl)oxy)phenyl)(phenyl)methanone is prepared by reacting 4-hydroxy benzophenone with 1,6-dibromohexane by using a base in a fluid medium at a temperature in the range of 20°C to 40°C for a time period in the range of 2 to 20 hours to obtain crude 4-((6-bromohexyl)oxy)phenyl(phenyl) methanone.
3. The process as claimed in claim 2, wherein said base is selected from potassium carbonate, sodium carbonate, lithium carbonate and cesium carbonate.

4. The process as claimed in claim 2, wherein said fluid medium is selected from dimethyl formamide (DMF), dimethyl sulfoxide (DMSO), dimethylacetamide (DMAc), N-methyl-2-pyrrolidone (NMP) and acetonitrile (ACN).
5. The process as claimed in claim 2, wherein a molar ratio of 4-hydroxy benzophenone to 1,6-dibromohexane is in the range of 1:1.5 to 1:10.
6. The process as claimed in claim 1, wherein said first fluid medium is selected from hexane and chloroform.
7. The process as claimed in claim 1, wherein said first predetermined temperature is in the range of 40°C to 70°C.
8. The process as claimed in claim 1, wherein said first predetermined time period is in the range of 10 to 15 hours.
9. The process as claimed in claim 1, wherein said base is selected from triethylamine (TEA), picoline and pyridine.
10. The process as claimed in claim 1, wherein said second fluid medium is selected from dichloromethane and ethylenedichloride.
11. The process as claimed in claim 1, wherein said second predetermined temperature is in the range of -5°C to 10°C
12. The process as claimed in claim 1, wherein said second predetermined time period is in the range of 0.5 hour to 2 hours.
13. The process as claimed in claim 1, said third fluid medium is selected from ethanol, methanol, propanol, butanol and ethyl acetate.
14. The process as claimed in claim 1, wherein said third predetermined temperature is in the range of 35°C to 50°C.

15. The process as claimed in claim 1, wherein said third predetermined time period is in the range of 10 to 20 hours.
16. The process as claimed in claim 1, wherein said quaternary ammonium compound is 6-(4-benzophenoxy)-N-(2-(decylamino)-2-oxoethyl)-N,N-dimethylhexane-1-ammonium bromide.
17. The process as claimed in claim 1, wherein a molar ratio of 4-((6-(dimethylamino)hexyl)oxyphenyl (phenyl)methanone to 2-bromo-N-decyl acetamide is in the range of 1:1.05 to 1:1.5.
18. The process as claimed in claim 1, wherein said quaternary ammonium compound has a purity greater than 98% and a yield in the range of 75 to 95%.