Claims:WE CLAIM:
1. Compound of Formula-I,

wherein R1, R2 and R3 are alkyl groups, and are independently selected from the group consisting of methyl, ethyl, propyl, butyl, pentyl and hexyl; and
X is selected from the group consisting of trifluoromethanesulfonyl, nonaflate, methanesulfonyl and toluenesulfonyl group.
2. The compound as claimed in claim 1, wherein X is trifluoromethanesulfonyl group.
3. A process for the preparing compounds of Formula-I,

wherein R1, R2 and R3 are alkyl groups, and are independently selected from the group consisting of methyl, ethyl, propyl, butyl, pentyl and hexyl; and X is selected from the group consisting of trifluoromethanesulfonyl, nonaflate, methanesulfonyl and toluenesulfonyl group;
said process comprising the following steps,
a. acylating 4-alkylphenol (II) using an acylating agent to obtain 4-alkylphenyl ester (III), followed by thermal treatment of III in the presence of a Lewis acid to obtain 2-acyl-4-alkylphenol (IV);
b. reducing IV using hydrazine in the presence of an alkali to obtain 2,4-dialkylphenol (V);
c. acylating V using an acylating agent to obtain 2,4-dialkylphenyl ester (VI) followed by thermal treatment of VI in the presence of a Lewis acid to obtain 6-acyl-2,4-dialkylphenol (VII);
d. reducing VII using hydrazine in the presence of an alkali to obtain 2,4,6-trialkylphenol (VIII); and
e. sulfonylating VIII with a sulfonylating agent in the presence of a first base to obtain compound of Formula-I.

4. The process as claimed in claim 3, wherein the acylating agent is at least one selected from the group consisting of acetyl chloride and acetic anhydride; wherein the molar ratio of II or V to the acylating agent is in the range of 1:1 to 1:1.5.
5. The process as claimed in claim 3, wherein the Lewis acid is at least one selected from the group consisting of aluminum chloride, boron trihydride, boron trifluoride, boron trichloride, boron tribromide, aluminium hydride, trimethyl aluminium, trimethyl boron, dimethyl beryllium and sulfur trioxide; wherein the molar ratio of III or VI to the Lewis acid is in the range of 1:1 to 1:2.
6. The process as claimed in claim 3, wherein the step of thermal treatment is carried out in at least one fluid medium selected from the group consisting of dichloroethane, methylene dichloride and carbon tetrachloride.
7. The process as claimed in claim 3, wherein the molar ratio of IV or VII to hydrazine is 1:1.5.
8. The process as claimed in claim 3, wherein the alkali is at least one selected from the group consisting of potassium hydroxide, sodium hydroxide and magnesium hydroxide; wherein the molar ratio of IV or VII to the alkali is in the range of 1:1 to 1:1.5.
9. The process as claimed in claim 3, wherein the step of reducing IV or VII is carried out in a fluid medium selected from the group consisting of diethylene glycol and monoethylene glycol.
10. The process as claimed in claim 3, wherein the step of reduction is carried out at a temperature in the range of 110 ?C to 250 ?C.
11. The process as claimed in claim 3, wherein the sulfonylating agent is a trifluoromethanesulfonylating agent, and the compound of formula-I is 2,4,6-trialkylphenyl trifluoromethanesulfonate.
12. The process as claimed in claim 3, wherein the first base is at least one selected from the group consisting of pyridine, alkyl amines, azoles, and metal carbonates.
13. A process for preparing dialkyl 2-(2,4,6-trialkylphenyl)malonate esters represented by Formula-IX from the compound of formula- I,

wherein R1, R2, R3 and R4 are alkyl groups independently selected from the group consisting of methyl, ethyl, propyl, butyl, pentyl and hexyl;
said process comprises nucleophilically substituting IX with dialkyl malonate (X) using a second base, and in the presence of a metal catalyst.
14. The process as claimed in claim 13, wherein the dialkyl malonate is diethyl malonate.
15. The process as claimed in claim 13, wherein the second base is at least one selected from the group consisting of sodium hydride, potassium carbonate and sodium carbonate, wherein the molar ratio of IX to the second base is in the range of 1:1 to 1:2.
16. The process as claimed in claim 13, wherein the metal catalyst is at least one selected from the group consisting of copper, copper iodide, copper chloride, copper bromide, cuprous iodide, chloride, cuprous bromide, copper carbonate, basic copper carbonate, copper oxide, zinc salts, iron salts, Pd, Pt, Ru, Rh, V, and Ir; wherein the molar ratio of I to the metal catalyst is in the range of 0.5:1 to 3:1.
17. The process as claimed in claim 13, wherein the nucleophilic substitution is carried out in n-methylpyrollidine as a fluid medium.
, Description:FIELD
The present disclosure relates to sulfonyl 2,4,6-trialkylbenzene compounds and process for their manufacturing.
BACKGROUND
Sulfonyl 2,4,6-trialkylbenzene compounds represented by Formula-I are important synthetic intermediates.

(I)
In Formula-I, R1, R2, and R3 are alkyl groups independently selected from the group consisting of methyl, ethyl, propyl, butyl, pentyl and hexyl. X is selected from the group consisting of trifluoromethanesulfonyl, nonaflate, methanesulfonyl and toluenesulfonyl group.
Conventional processes for the synthesis of I are associated with drawbacks such as use of costly chemicals and reagents, use of high pressure reactions, use of hetero-phase reaction of hydrogen chloride and using complex plant set up.
There is, therefore, felt a need to develop a simple, and economic process for manufacturing sulfonyl 2,4,6-trialkylbenzene compounds.

OBJECTS
Some of the objects of the present disclosure, which at least one embodiment herein satisfies, are as follows:
It is an object of the present disclosure 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 sulfonyl 2,4,6-trialkylbenzene compounds.
Yet another object of the present disclosure is to provide a simple, and economic process for manufacturing sulfonyl 2,4,6-trialkylbenzene compounds.
Still another object of the present disclosure is to provide a process for synthesis of dialkyl 2-(2,4,6-trialkylphenyl)malonate esters from sulfonyl 2,4,6-trialkylbenzene compounds.
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
In one aspect, the present disclosure provides compounds of Formula-I,

wherein R1, R2 and R3 are alkyl groups, and are independently selected from the group consisting of methyl, ethyl, propyl, butyl, pentyl and hexyl; and
X is selected from the group consisting of trifluoromethanesulfonyl, nonaflate, methanesulfonyl and toluenesulfonyl group.
In second aspect, the present disclosure provides a process for the preparation of sulfonyl 2,4,6-trialkylbenzene compounds (I). The process comprises the following steps,
a. acylating 4-alkylphenol (II) using an acylating agent to obtain 4-alkylphenyl ester (III), followed by thermal treatment of III in the presence of a Lewis acid to obtain 2-acyl-4-alkylphenol (IV);
b. reducing IV using hydrazine in the presence of an alkali to obtain 2,4-dialkylphenol (V);
c. acylating V using an acylating agent to obtain 2,4-dialkylphenyl ester (VI) and thermal treatment of VI in the presence of a Lewis acid to obtain 6-acyl-2,4-dialkylphenol (VII);
d. reducing VII using hydrazine in the presence of an alkali to obtain 2,4,6-trialkylphenol (VIII); and
e. sulfonylating VIII with a sulfonylating agent in the presence of first base to obtain compound of Formula-I.

In third aspect, the present disclosure provides a process for preparing dialkyl 2-(2,4,6-trialkylphenyl)malonate esters represented by Formula-IX from the sulfonyl 2,4,6-trialkylbenzene compounds of formula- I,

wherein R1, R2, R3 and R4 are alkyl groups independently selected from the group consisting of methyl, ethyl, propyl, butyl, pentyl and hexyl.
The process comprises nucleophilically substituting IX with dialkyl malonate (X) using a second base, and in the presence of a metal catalyst.

DETAILED DESCRIPTION
Sulfonyl 2,4,6-trialkylbenzene compounds, represented by Formula-I, are important synthetic intermediates. Conventional processes for the synthesis of compounds of formula I use high pressure reactions, and complex plant set up. Therefore, the conventional processes are costly, and complex.
The present disclosure envisages compounds of Formula-I and a simple process for preparation thereof.
In an aspect, the present disclosure provides compounds of Formula-I,

wherein R1, R2 and R3 are alkyl groups, and are independently selected from the group consisting of methyl, ethyl, propyl, butyl, pentyl and hexyl; and
X is selected from the group consisting of trifluoromethanesulfonyl, nonaflate, methanesulfonyl and toluenesulfonyl group.
Compounds of Formula-I comprising X as a halogen selected from the group consisting of chloride, bromide and iodide can also be prepared.
In one embodiment of the present disclosure, in the compound of Formula I, X is trifluoromethanesulfonyl group.
In one embodiment of the present disclosure, in the compound of Formula I, R1, R2 and R3 are alkyl groups, and are independently selected from the group consisting of methyl, ethyl and propyl.
In one embodiment of the present disclosure, in the compound of Formula I, R1 consists of alkyl groups which can be independently selected from methyl, ethyl, propyl, butyl, pentyl and hexyl.
In one embodiment of the present disclosure, in the compound of Formula I, R2 consists of alkyl groups which can be independently selected from methyl, ethyl, propyl, butyl, pentyl and hexyl.
In one embodiment of the present disclosure, in the compound of Formula I, R3 consists of alkyl groups which can be selected from methyl, ethyl, propyl, butyl, pentyl and hexyl.
In second aspect, the present disclosure provides a process for the preparation of compounds of formula I. The process is provided in Scheme 1.
Scheme 1: Process for synthesis of I

In scheme 1, R1, R2, and R3 are alkyl groups, and are independently selected from the group consisting of methyl, ethyl, propyl, butyl, pentyl and hexyl. X is selected from the group consisting of trifluoromethanesulfonyl, nonaflate, methanesulfonyl and toluenesulfonyl group.
The steps of reduction of IV to V and reduction of VII to VIII involve reduction of an acyl group to corresponding alkyl group. Conventional processes for reduction of an acyl group to corresponding alkyl group are associated with drawbacks such as use of hydrogen gas under high pressure, and use of costly catalysts. Further, the yield of the conventional process is low. Due to the use of hydrogen gas under high pressure, the conventional processes require special reactor and use of complex plant set up. Additionally, the use of hydrogen gas under high pressure is dangerous.
In the present disclosure, the reduction of acyl group to alkyl group is carried out using hydrazine as reducing agent. In the process of the present disclosure, the use of hydrogen gas is avoided, and therefore, plant set up is simple and there is no need to use of a specialized assembly. Further, the reduction is safe, and provides high yield.
More specifically, the process of the present disclosure for the synthesis of I involves the following steps:
The first step involves acylation of 4-alkylphenol (II) using an acylating agent to obtain 4-alkylphenyl ester (III), followed by thermal treatment of III in the presence of a Lewis acid to obtain 2-acyl-4-alkylphenol (IV).
Step-1: Preparation of 2-acyl-4-alkylphenol (IV)

In the structures II, III and IV, R1 and R2 are alkyl groups independently selected from the group consisting of methyl, ethyl, propyl, butyl, pentyl and hexyl.
The yield of IV is in the range of 80 % to 97%.
The second step is reduction of IV using hydrazine in the presence of an alkali to obtain 2,4-dialkylphenol (V).
Step-2: Preparation of 2,4-dialkylphenol (V)

In structures IV and V, R1 and R2 are alkyl groups independently selected from the group consisting of methyl, ethyl, propyl, butyl, pentyl and hexyl.
The yield of V is in the range of 50 % to 75%.
Third step involves acylation of V using an acylating agent to obtain 2,4-dialkylphenyl ester (VI) followed by thermal treatment of VI in the presence of a Lewis acid to obtain 6-acyl-2,4-dialkylphenol (VII).
Step-3: Preparation of 6-acyl-2,4-dialkylphenol (VII)

In structures V, VI and VII, R1, R2 and R3 are alkyl groups independently selected from the group consisting of methyl, ethyl, propyl, butyl, pentyl and hexyl.
The yield of VII is in the range of 80 % to 97%.
The fourth step involves reduction of VII using hydrazine in the presence of an alkali to obtain 2,4,6-trialkylphenol (VIII).
Step-4: Preparation of 2,4,6-trialkylphenol (VIII)

In structures VII, and VIII, R1, R2 and R3 are alkyl groups independently selected from the group consisting of methyl, ethyl, propyl, butyl, pentyl and hexyl.
The yield of VIII is in the range of 50 % to 75%.
The fifth step is sulfonylation of VIII with a sulfonylating agent in the presence of a first base to obtain compound of Formula-I.
Step-5: Preparation of derivatives of 2,4,6-trialkylbenzene (I)

In structures VIII, and I, R1, R2 and R3 are alkyl groups independently selected from the group consisting of methyl, ethyl, propyl, butyl, pentyl and hexyl. X is selected from the group consisting of trifluoromethanesulfonyl, nonaflate, methanesulfonyl and toluenesulfonyl group.
In accordance with the embodiments of the present disclosure, the acylating agent is at least one selected from the group consisting of acetyl chloride and acetic anhydride.
The molar ratio of II or V to the acylating agent is in the range of 1:1 to 1:1.5, preferably 1:1.2.
The acylating agent used for acylating II and the acylating agent used for acylating V are same or different.
The Lewis acid is at least one selected from the group consisting of aluminum chloride, boron trihydride, boron trifluoride, boron trichloride, boron tribromide, aluminium hydride, trimethyl aluminium, trimethyl boron, dimethyl beryllium and sulfur trioxide.
The molar ratio of III or VI to the Lewis acid is in the range of 1:1 to 1:2, preferably 1:1.5.
The Lewis acid used for acylating II and the Lewis acid used for acylating V are same or different.
The sub-step of thermal treatment is carried out in at least one fluid medium selected from the group consisting of dichloroethane, methylene dichloride and carbon tetrachloride.
In accordance with one embodiment of the present disclosure, the sub-step of thermal treatment of III is carried out under reflux in dichloroethane as a fluid medium for 36 hours.
The molar ratio of IV to hydrazine is in the range of 1:1 to 1:2.5, preferably 1:1.5.
The alkali is at least one selected from the group consisting of potassium hydroxide, sodium hydroxide and magnesium hydroxide.
The molar ratio of IV or VII to the alkali is in the range of 1:1 to 1:1.5.
In accordance with one embodiment of the present disclosure, the molar ratio of IV or VII to the alkali is 1:1.2.
The alkali used in step of reducing IV and the alkali used in step of reducing VII are same or different.
The step of reduction is carried out in a fluid medium selected from the group consisting of diethylene glycol and monoethylene glycol.
The step of reduction is carried out at a temperature in the range of 110 ?C to 250 ?C.
Preferably, the step of reduction is carried out at a temperature in the range of 125 ?C to 225 ?C.
The step of reduction is carried out for a time period in the range of 4 hours to 20 hours.
The molar ratio of VIII to the sulfonylating agent is in the range of 1:1 to 1:2.
In accordance with one embodiment of the present disclosure, the molar ratio of VIII to the sulfonylating agent is 1:1.5.
The first base is at least one selected from the group consisting of pyridine, alkyl amines, azoles, and metal carbonates.
The molar ratio of VIII to the first base is in the range of 1:1 to 1:2.
In accordance with one embodiment of the present disclosure, the molar ratio of VIII to the first base is 1:1.5.
The step of sulfonylation is carried out in at least one fluid medium selected from the group consisting of dichloromethane, methylene dichloride and carbon tetrachloride.
In one embodiment of the present disclosure, X is trifluoromethanesulfonyl group. The sulfonylating agent is a trifluoromethanesulfonylating agent, and compound of formula-I is 2,4,6-trialkylphenyl trifluoromethanesulfonate.
The trifluoromethanesulfonylating agent is trifluoromethanesulfonyl anhydride.
The yield of I is in the range of 70 % to 90%.
In third aspect, the present disclosure provides a process for preparing dialkyl 2-(2,4,6-trialkylphenyl)malonate esters represented by Formula-IX.

(IX)
In Formula IX, R1, R2, R3 and R4 are alkyl groups independently selected from the group consisting of methyl, ethyl, propyl, butyl, pentyl and hexyl.
In one embodiment of the present disclosure, in the compound of Formula IX, R1, R2, R3 and R4 are alkyl groups, and are independently selected from the group consisting of methyl, ethyl and propyl.
In one embodiment of the present disclosure, in the compound of Formula IX, R1 consists of alkyl groups which can be independently selected from methyl, ethyl, propyl, butyl, pentyl and hexyl.
In one embodiment of the present disclosure, in the compound of Formula IX, R2 consists of alkyl groups independently selected from methyl, ethyl, propyl, butyl, pentyl and hexyl.
In one embodiment of the present disclosure, in the compound of Formula IX, R3 consists of alkyl groups independently selected from methyl, ethyl, propyl, butyl, pentyl and hexyl.
In one embodiment of the present disclosure, in the compound of Formula IX, R4 consists of alkyl groups independently selected from methyl, ethyl, propyl, butyl, pentyl and hexyl.
The synthesis of IX using the process of the present disclosure involves nucleophilic substitution of IX with dialkyl malonate (X) using a second base, and in the presence of a metal catalyst to obtain IX. The process is represented as Scheme 2.
Scheme 2: Synthesis of IX

In structures I, X and IX, R1, R2, R3 and R4 are alkyl groups independently selected from the group consisting of methyl, ethyl, propyl, butyl, pentyl and hexyl.
The dialkyl malonate is diethyl malonate. The molar ratio of IX to the dialkyl malonate is in the range of 1:1 to 1:1.5.
In accordance with one embodiment of the present disclosure, the molar ratio of IX to the dialkyl malonate is 1:1.
The second base is at least one selected from the group consisting of sodium hydride, potassium carbonate and sodium carbonate.
The molar ratio of IX to the second base is in the range of 1:1 to 1:2, preferably 1:1.3.
The metal catalyst is at least one selected from the group consisting of copper, copper iodide, copper chloride, copper bromide, cuprous iodide, chloride, cuprous bromide, copper carbonate, basic copper carbonate, copper oxide, zinc salts, iron salts, Pd, Pt, Ru, Rh, V, and Ir.
The molar ratio of I to the metal catalyst is in the range of 0.5:1 to 3:1.
In accordance with the embodiments of the present disclosure, the molar ratio of I to the metal catalyst is 1:1 to 1:1.5.
The step of nucleophilic substitution is carried out in n-methylpyrollidine as a fluid medium.
The step of nucleophilic substitution is carried out at a temperature in the range of 70 ?C to 150 ?C.
The yield of IX is up to 80%.
The process of the present disclosure uses readily available and cheap chemicals and reagents. Further, the use of expensive materials such as Palladium acetate is avoided. Thus, the process of the present disclosure is cost effective.
The process of the present disclosure does not involve the use of a high pressure reaction, or use of hetero-phase involving gaseous HCl. Therefore, the process of the present disclosure is safe.
Furthermore, the process of the present disclosure can be easily scaled up.
The present disclosure is further described in light of the following experiments which are set forth for illustration purpose only and not to be construed for limiting the scope of the disclosure. The following experiments can be scaled up to industrial/commercial scale and the results obtained can be extrapolated to industrial scale.
Experimental details:
Step 1: Preparation of 2-acetyl-4-alkylphenol (IV)
Acetyl choride (79 mL, 1.2 eq.) was added dropwise to p-Cresol (100 g, 1 eq) at 0 ?C over a period of 30 minutes and the resultant mixture was stirred at 20 ?C for 4 hours. After 4 hours, unreacted acetyl chloride was removed employing a rotary evaporator. The product obtained, 4-methylphenyl acetate (III), was used as such for further reaction.
1,2-Dichloroethane (400 mL, 4 volumes) was added to III and the resultant mixture was cooled to 5 ?C. The cooled mixture was vigorously stirred at 5 ?C, while AlCl3 (133 g, 1.5 eq.) was added to the cooled mixture in 3 lots over a period of 1 hour. The reaction mixture was heated under reflux for 36 hours to obtain a product mixture.
The product mixture was cooled and then quenched in cold dilute HCl (500 mL, 10 volumes). The resultant mixture was extracted thrice with chloroform (150 mL, 2 volumes each time). The organic layers were combined and the combined organic layer was washed with water, and then with brine solution. The volatiles were removed from the organic layer employing a rotary evaporator to obtain 2-acetyl-4-methylphenol (IV) with 93% yield.

Step-2: Preparation of 2-ethyl-4-methylphenol (V)
IV (70 g, 1.0 eq.), diethylene glycol (280 mL, 4 vol), hydrazine hydrate (43 mL, 1.5 eq) and KOH (28 g, 1.2 eq) were mixed and stirred for 5 minutes. The resultant mixture was heated at 140 ?C for 3 hours. This step was followed by removal of hydrazine hydrate and water employing a rotary evaporator to obtain a residue. The residue was further heated at 200 ?C for 3 hours to obtain a product mixture. The product mixture was poured on cold water with continuous stirring. The product was extracted with diethyl ether and the organic layer was washed with water. The volatiles were removed from the organic layer employing a rotary evaporator to obtain 2-ethyl-4-methylphenol (V) in 65% yield.

Step-3: Preparation of 2-ethyl-4-methylphenyl acetate (VII)
2-Ethyl-4-methyl phenol (50 g, 1.0 eq.) and dichloromethane (200 mL, 4 vol.) were mixed and the mixture was cooled to 0 ?C and stirred for 5 minutes. Acetyl chloride (43 mL, 1.5 eq.) was added dropwise to the cooled mixture over a period of 30 minutes to obtain a reaction mixture. The reaction mixture was stirred at room temperature for 2 hours to obtain a product mixture. The volatiles were removed from the product mixture employing a rotary evaporator to obtain 2-ethyl-4-methylphenyl acetate (VII) in 87% yield. The product was used for the next reaction as such.

2-Ethyl-4-methylphenyl acetate (40 g, 1 eq.) and 1,2-dichloroethane (160 mL, 4 vol) were mixed and the mixture was cooled to 0 ?C. AlCl3 (45 g, 1.5 eq.) was added to the cooled mixture in 3 lots over a period of 1 hour under vigorous stirring at 0 ?C to obtain a reaction mixture. The reaction mixture was refluxed for 36 hours to obtain a product mixture. The product mixture was cooled and quenched with cold dilute HCl (200 mL, 10 vol.). The quenched product mixture was extracted thrice with chloroform (100 mL, 2 vol.). The organic layers were combined and the combined organic layer was then washed with water and then with brine solution. The volatiles were removed employing a rotary evaporator to afford 1-(3-ethyl-2-hydroxy-5-methylphenyl)ethan-1-one (VII) with 90% yield.

Step-4: Preparation of 2,6-diethyl-4-methylphenol (VIII)
1-(3-Ethyl-2-hydroxy-5-methylphenyl)ethan-1-one (35 g, 1.0 eq), diethylene glycol (140 mL, 4 vol), hydrazine hydrate (19 mL, 1.5 eq.) and KOH (14 g, 1.2 eq) were mixed and the mixture was stirred for 5 minutes followed by heating at 140 ?C for 3 hours. After 3 hours, the volatiles were removed from the reaction mixture employing a rotary evaporator to obtain a residue. The residue was heated at 200 ?C for 3 hours to obtain a product mixture. The product mixture was poured on cold water, followed by extraction with diethyl ether. The organic layer was washed with water. The volatiles were removed employing a rotary evaporator to obtain 2,6-diethyl-4-methylphenol (VIII) in 65% yield.

Step-5: Preparation of 2,6-diethyl-4-methylphenyl trifluoromethanesulfonate (I)
2,6-Diethyl-4-methyl phenol (40 g, 1 eq), DCM (160 mL, 4 vol) and pyridine (30 mL, 1.5 eq), were mixed and the resultant mixture was stirred at room temperature for 15 minutes. Triflic anhydride (60 mL, 1.5 eq) was added dropwise to the mixture over a period of 30 minutes. After complete addition, the resultant mixture was stirred at room temperature for 10 hours to obtain a product mixture.
The product mixture was poured into dilute HCl to remove excess pyridine. The resultant mixture was extracted with chloroform. The organic layer was washed with water and then dried with sodium sulphate. The volatiles were removed employing a rotary evaporator to afford 2,6-diethyl-4-methylphenyl trifluoromethanesulfonate (I) in 80% yield.

Synthesis of diethyl 2-(2,6-diethyl-4-methylphenyl)malonate (IX)
To a stirred suspension of sodium hydride (3.6 g, 1.3 eq, 60% w/w dispersion in mineral oil) in 1-methyl-2-pyrrolidone (NMP, 16 mL) at 0 ?C, was added malonic acid diethyl ester (11 g, 1 eq.) in NMP (50 mL) dropwise over 3 hours. The mixture was stirred at room temperature for 12 hours to obtain sodium salt of diethyl malonate in NMP.
In another round bottom flask, 2,6-diethyl-4-methyl phenol triflate (I) (10 g, 1eq), NMP (80 mL, 8 vol) and copper iodide (5.94 g, 1 eq) were added, and the resultant mixture was heated at 80 ?C for 1 hour.
Sodium salt of diethyl malonate in NMP was added at once to the mixture obtained above, and the reaction mixture was heated at 100 ?C for 10 hours to obtain a product mixture.
The product mixture was poured on a cold 1 N HCl (10 vol) and ethyl acetate (10 vol) and stirred vigorously. The copper salts were filtered off to obtain filtrate. The filtrate was allowed to settle to obtain a biphasic mixture. The organic layer was separated. The aqueous phase was extracted twice with ethyl acetate. The combined organic layer was evaporated employing a rotary evaporator to obtain a residue. The residue was purified by chromatography on silica gel (ethyl acetate/hexane 1:5) to obtain IX in 62% yield.

TECHNICAL ADVANCEMENTS AND ECONOMICAL SIGNIFICANCE
The present disclosure described herein above has several technical advantages including, but not limited to, the realization of a novel intermediate and a process for the synthesis of sulfonyl 2,4,6-trialkylbenzene compounds,
- that is simple, and economic; and
- that is safe.

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.