DESC:FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENT RULES, 2003

COMPLETE SPECIFICATION
(See Section 10 and Rule 13)

Title of invention:
A PROCESS OF PREPARATION OF 3'-(TRIFLUOROMETHYL)ACETOPHENONE (TFMAP)

APPLICANT:
Deepak Nitrite Limited
An Indian entity
having address as:
Register & Corporate Office, Aaditya-1, Chhani Road, Vadodara-390024. Gujarat, India

The following specification describes the invention and the manner in which it is to be performed.

CROSS-REFERENCE TO RELATED APPLICATIONS AND PRIORITY
The present application claims priority from Indian patent application number 202221028493 filed on 18 May 2022, incorporated herein by a reference.
TECHNICAL FIELD
The present subject matter described herein, in general, relates to a process of preparation of 3'-(Trifluoromethyl)acetophenone (TFMAP). In particular, the present subject matter is related to the preparation of highly pure 3'-(Trifluoromethyl)acetophenone (TFMAP) with improved yield and purity.
BACKGROUND
Acetophenone derivative such as 3'-(Trifluoromethyl)acetophenone (hereinafter alternatively referred as “TFMAP”) is useful as an intermediate for the synthesis of agrochemicals compounds such as pesticidal, fungicidal compounds. TFMAP is used as an intermediate in the preparation of Trifloxystrobin which is used as a pesticide.

In state of the art, the conventional process of preparing TFMAP lack in many aspects such as loss of product, loss of reactants and reaction intermediates, time consumption and consumptions of high amount of energy.
Several patents have been filed for the preparation of 3'-(Trifluoromethyl) acetophenone with Trifluoromethylbenzene and n-Butyl Lithium as starting material. However, the Trifluoromethylbenzene and n-Butyl Lithium are pyrophoric by nature and challenging to manage at industrial scale manufacturing. Also, handling it on a commercial scale raises serious safety concerns because it could severely breakdown if exposed to air or moisture. As a result, such techniques are not practical or secure to use on a large scale.
Additionally, some processes use 60% sulfuric acid during the hydrolysis step, which results in lower yields due to increased contaminant production and higher COD in the spent effluent. The use of concentrated sulfuric acid results in higher caustic consumption standards to maintain the reaction mass's pH which will drive up the cost of production.
Therefore, there is a long felt need for developing an economic process for preparing 3'-(Trifluoromethyl) acetophenone (TFMAP) product by minimizing the reactants consumption, loss of reactants and reaction intermediates, thereby increasing the overall purity and yield of the final product i.e., 3'-(Trifluoromethyl)acetophenone (TFMAP).
OBJECTS OF THE INVENTION
The principal object of this invention is to provide a system for preparation of 3'-(Trifluoromethyl)acetophenone (TFMAP), enabled to provide a high yield and high purity of TFMAP.
Another object of this invention is to provide a process TFMAP enabled to provide high yield and high purity of TFMAP.
Yet another object of this is invention is to provide a process enabled to selectively use AAO (50% solution in water) for easy and safe handling at commercial scale.
Still another object of this invention is to provide a process for simultaneous recovery of the solvents and byproduct such as 3- hydroxybenzotrifluoride.
Yet another object of this invention is to provide a process for preparing 3'-(Trifluoromethyl)acetophenone (TFMAP) with minimum effluent generation.
SUMMARY
This summary is provided to introduce concepts related to a system and process for preparation of 3'-(Trifluoromethyl)acetophenone (TFMAP). This summary is not intended to identify essential features of the claimed subject matter, nor it is intended for use in determining or limiting the scope of the disclosed subject matter.
In accordance with an embodiment of the present subject matter, a system and process TFMAP enabled to provide high yield and high purity of TFMAP.
In one embodiment, a system for preparation of a 3’-(Trifluoromethyl) acetophenone (TFMAP) is disclosed. The system may comprise a first reactor enabled for the preparation of a diazo solution from reacting 3-aminobenzotrifluoride and sulfuric acid in the presence of toluene and sodium nitrite (NaNO2) solution; a second reactor enabled for the mixing and lot-wise addition of acetaldoxime solution and the diazo solution, followed by addition of other reactants to obtain an aqueous layer and organic layer i.e., 3’-(Trifluoromethyl)acetophenone oxime; a third reactor enabled for the hydrolysis reaction of the 3’-(Trifluoromethyl) acetophenone oxime with the 30% HCl to obtain a 3’-(Trifluoromethyl) acetophenone (TFMAP); and a distillation unit in association with the third reactor configured for obtaining a refined 3'-(Trifluoromethyl) acetophenone (TFMAP).
In yet another embodiment, a 3’-(Trifluoromethyl) acetophenone (TFMAP) product obtained by implementing the system and process as disclosed herein, comprising: appearance ranging from colourless to orange liquid; purity in the range of 99-99.9%; and yield in the range of 60-90%.
In still another embodiment, a process for preparing a 3-(Trifluoromethyl) acetophenone (TFMAP), comprises the following steps is disclosed. The process may comprise a step of introducing water in a first reactor, followed by reacting 3-aminobenzotrifluoride (3-ABTF) with sulfuric acid (H2SO4) in the presence of toluene and sodium nitrite (NaNO2) solution to obtain a reaction mass A. The next step may comprise of adding sulfamic acid dissolved in water in the reaction mass A with constant stirring, followed by heating at 7-8 °C to obtain a diazo solution in the first reactor. The process may comprise a step of coupling the diazo solution and acetaldoxime solution in a lot-wise manner in a second reactor with constant stirring for 4-5 hr, followed by incorporation of other reactants to obtain a reaction mass B having an aqueous layer and organic layer of 3’-(Trifluoromethyl)acetophenone oxime. The process may further comprise a step of elevating the temperature up to 35-40 °C to separate the organic layer from the aqueous layer in the reaction mass B, followed by washing the organic layer with 30% hydrochloric acid solution to obtain a 3'-(Trifluoromethyl)acetophenone oxime. In the next step the process may comprise a step of feeding 3'-(Trifluoromethyl) acetophenone oxime in a third reactor, followed by addition of 30% hydrochloric acid solution with constant stirring to obtain a crude 3'-(Trifluoromethyl) acetophenone (TFMAP) containing aqueous effluent layer and crude organic layer. The process may further comprise a step of distilling the crude organic layer of the reaction mass B in a distillation unit to obtain a refined 3'-(Trifluoromethyl) acetophenone (TFMAP).
In yet another embodiment, the 3-(Trifluoromethyl) acetophenone (TFMAP) is prepared by a batch process.
List of Abbreviations
3-ABTF: 3-aminobenzotrifluoride
H2SO4: sulfuric acid
NaNO2: sodium nitrite
ETP: Effluent plant treatment
TFMAP: 3'-(Trifluoromethyl) acetophenone
AAO: Acetaldoxime
HCl: Hydrochloric acid
BRIEF DESCRIPTION OF DRAWINGS
The detailed description is described with reference to the accompanying Figures. In the Figures, the left-most digit(s) of a reference number identifies the Figure in which the reference number first appears. The same numbers are used throughout the drawings to refer like features and components.
Figure 1 depicts a system (100) for the preparation of 3'-(Trifluoromethyl) acetophenone, in accordance with an embodiment of the present subject matter.
Figure 2 depicts a flowchart for working of the system (100) for the preparation of 3'-(Trifluoromethyl) acetophenone, in accordance with an embodiment of the present subject matter.
Figure 3 depicts a process (300) for the preparation of 3'-(Trifluoromethyl) acetophenone, in accordance with an embodiment of the present subject matter.
DETAILED DESCRIPTION
Reference throughout the specification to “various embodiments,” “some embodiments,” “one embodiment,” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, appearances of the phrases “in various embodiments,” “in some embodiments,” “in one embodiment,” or “in an embodiment” in places throughout the specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures or characteristics may be combined in any suitable manner in one or more embodiments.
The words "comprising," "having," "containing," and "including," and other forms thereof, are intended to be equivalent in meaning and be open ended in that an item or items following any one of these words is not meant to be an exhaustive listing of such item or items or meant to be limited to only the listed item or items. It must also be noted that, the singular forms "a," "an," and "the" include plural references unless the context clearly dictates otherwise. Although any process similar or equivalent to those described herein can be used in the practice or testing of embodiments of the present disclosure, the exemplary process are described. The disclosed embodiments are merely exemplary of the disclosure, which may be embodied in various forms.
Various modifications to the embodiment may be readily apparent to those skilled in the art and the generic principles herein may be applied to other embodiments. However, one of ordinary skill in the art may readily recognize that the present disclosure is not intended to be limited to the embodiments illustrated but is to be accorded the widest scope consistent with the principles and features described herein. The detailed description of the invention will be described hereinafter referring to accompanied drawings.
In one embodiment of the present invention, referring figure 1, a system (100) for preparing a 3’-(Trifluoromethyl) acetophenone (TFMAP) is illustrated in accordance with the embodiments of the present invention.
In one embodiment of the present invention, by referring to figure 1 & figure 2, the system (100) for preparation of a 3’-(Trifluoromethyl) acetophenone (TFMAP) is disclosed. The system (100) may comprise a first reactor (104) enabled for the preparation of a diazo solution by reacting 3-aminobenzotrifluoride and sulfuric acid (obtained from the tank (101)) in the presence of toluene and sodium nitrite (NaNO2) solution obtained from the tank (102). The said system (100) further may comprise a second reactor (105) enabled for the lot-wise mixing of acetaldoxime solution obtained from tank (103) with the lot-wise addition of diazo solution in a second reactor (105) in a predetermined amount, followed by addition of other reactants i.e., a mixture of water, copper (II) sulfate, glacial acetic acid and toluene obtained from tank (107) to obtain 3’-(Trifluoromethyl)acetophenone oxime.
The said system (100) further may comprise a third reactor (110) enabled for the hydrolysis reaction of 3’-(Trifluoromethyl) acetophenone oxime with the 30% HCl from tank (108) to obtain 3’-(Trifluoromethyl) acetophenone (TFMAP). The third reactor (110) is further configured for layer separation of an aqueous effluent layer and crude organic layer of 3'-(Trifluoromethyl) acetophenone (TFMAP). Moreover, the third reactor is configured for transferring the aqueous effluent layer to an effluent treatment plant (112) enabled to retrieve additional 3'-(Trifluoromethyl) acetophenone by treating the aqueous layer from the third reactor (105).
In one embodiment, the said system (100) may comprise a tank (111) configured for alkaline washing of the crude organic layer of 3'-(Trifluoromethyl) acetophenone (TFMAP) from the third reactor (110) by 3-10% and preferably 3-7% NaOH added from reactor (106) in alkali washing tank (111) to remove residual acidity and transfer the crude organic layer of TFMAP to distillation unit (113).
The said system (100) may further be connected to a distillation unit (113) in association with the third reactor (110) configured for obtaining a refined and pure 3'-(Trifluoromethyl) acetophenone (TFMAP).
In another embodiment of the present invention, referring figure 3, a process (300) for preparing a 3'-(Trifluoromethyl) acetophenone (TFMAP) is illustrated in accordance with the embodiments of the present invention. The process (300) of preparation of 3'-(Trifluoromethyl) acetophenone (TFMAP) comprises of various steps and further divided into four stages. In one embodiment, the process (300) is a batch process particularly enabled for large scale production of TFMAP.
In one embodiment of the present invention, in the first stage A the process (300) may comprise a step of diazotization 3-aminobenzotrifluoride (3-ABTF) to obtain diazo Solution. In the second stage B, the process may comprise a step of coupling the said diazo solution with acetaldoxime solution to obtain 3'-(Trifluoromethyl)acetophenone oxime. In the third stage C, the process (300) may comprise of hydrolysis of 3'-(Trifluoromethyl) acetophenone oxime to obtain 3'-(Trifluoromethyl) acetophenone (TFMAP). In the fourth stage D, distillation of crude organic layer of 3'-(Trifluoromethyl) acetophenone to obtain refined 3'-(Trifluoromethyl) acetophenone (TFMAP).
A first stage of Preparation of Diazo Solution (Diazotization reaction)- Stage (A)
In one embodiment of the present invention, the process (300) may include a stage of preparation of Diazo Solution stage (A) in the first reactor (104). The first stage (A) may comprise a step of introducing (301) water in a first reactor (104), followed by reacting 3-aminobenzotrifluoride (3-ABTF) with sulfuric acid (H2SO4) in the presence of toluene and sodium nitrite (NaNO2) solution to obtain a reaction mass A.
The first stage (A) further may comprise a step of stirring the above obtained reaction mass for a predetermined time period of 1-4 hrs and preferably 30-45 minutes and maintaining temperature of the diazotization reaction between -5 to 10 °C and preferably 0-2 °C. The first stage (A) may further comprise a sub-step of adding (302) the sulfamic acid dissolved in water to decompose excess sodium nitrite and remove excess of NOx. In an optional embodiment, sodium silicate is added to the reaction for prevention of glass of the reactor and to ensure safety. In one embodiment, the first stage (A) is enabled to recover 90-98% of toluene from the reaction. The first stage (A) further may comprise a step of cooling of the Diazo solution and storing at 7-8 °C.
A second stage of Preparation of 3'-(Trifluoromethyl) acetophenone oxime (Coupling)- Stage (B)
In yet another embodiment of the present invention, the process (300) may comprise a second stage (B) of coupling (303) of the said diazo solution with acetaldoxime solution from the tank (103) to obtain B 3'-(Trifluoromethyl) acetophenone oxime (a reaction mass B) in a second reactor (105). The second stage (B) may comprise a step of adding acetaldoxime solution (50% solution in water) 0.8 to 1.5 mole equivalent in lot-wise manner with constant stirring for 4-5 Hr to a reaction mixture comprising diazo solution, water, copper (II) sulfate, glacial acetic acid, and toluene at a constant temperature between 0-2 °C. Acetaldoxime (AAO) is sensitive to the pH of the reaction, and at acidic pH the AAO is degraded concurrently, resulting in a lower yield. The lot wise addition of AAO followed by lot wise addition of diazo solution is employed to retain a specific concentration of the AAO available and recover the product 3- hydroxybenzotrifluoride, resulting in enhanced yield and less contamination over the conventional plant process.
Further, the second stage (B) may comprise a step of repetitive lot-wise slow addition of 25% quantity of diazo solution at least for four times by maintaining temperature between 0-2 °C and pH within the range of 2 to 2.5 followed by addition of acetaldoxime solution (50% solution in water) from the tank (103) at each of the lot-wise slow addition, wherein the pH of the reaction mass may be raised at 3-3.5 during the addition of the said acetaldoxime solution by addition of

30% NaOH at each of the lot-wise slow addition, wherein the reaction mass is stirred for further 4-5 Hrs. The acetaldoxime is added in 4-5 parts in first addition, followed by 1-2 parts in second and third addition and ultimately addition of 2-3 parts in the fourth addition of the total addition quantity divided in 8-12 parts. In an embodiment, wherein for lot wise addition of acetaldoxime pH is adjusted between 2 to 2.5 for first and second lot, and between 3 to 3.5 for third and fourth lot.
The second stage (B) further may comprise a step of separating the bottom aqueous layer and remaining organic layer by elevating (304) the temperature up to 35-40 °C.
A third stage of preparation of 3'-(Trifluoromethyl) acetophenone (TFMAP) (Hydrolysis)- Stage (C)
In still another embodiment of the present invention, the process (300) may comprise a third stage (C) of hydrolysis of 3'-(Trifluoromethyl) acetophenone oxime to obtain 3'-(Trifluoromethyl) acetophenone (TFMAP). The third stage (C) may comprise a step of feeding (305) 3'-(Trifluoromethyl) acetophenone oxime in a third reactor (110). The third stage may further comprise addition of a predefined quantity of 30% Hydrochloric acid (HCl) obtained from tank (108), and water from tank (109) and heating to a predetermined temperature between 70-110 °C and preferably 90-95 °C and for a predetermined period between 3-7 hours and preferably 5-6 with constant stirring to obtain a crude 3'-(Trifluoromethyl) acetophenone (TFMAP) containing aqueous effluent layer and crude organic layer. The third stage (C) further may comprise a step of alkali washing (306) of the said crude organic layer of TFMAP with water and 3-10% and preferably 3-7% sodium hydroxide (NaOH) added from tank (106) solution in the alkaline washing tank (111). The alkali washing (306) of the crude organic layer of TFMAP enables removal of residual acidity before distillation. The third stage (C) further may comprise a step of distilling (307) the crude organic layer of TFMAP in distillation unit (113) to obtain pure 3'-(Trifluoromethyl) acetophenone (TFMAP).
A fourth stage of additional recovery of 3'-(Trifluoromethyl) acetophenone (TFMAP) from effluent - Stage (D)
In still another embodiment of the present invention, the process (300) may comprise a fourth stage (D) of additional recovery of 3'-(Trifluoromethyl) acetophenone (TFMAP) from effluent. The fourth stage (D) may comprise a step of transferring bottom aqueous layer separated at second stage B to effluent treatment plant (ETP) (112). The fourth stage (D) further may optionally comprise transferring the aqueous effluent layer to an effluent treatment plant (112) enabled to retrieve additional 3'-(Trifluoromethyl) acetophenone by treating the aqueous layer from the third reactor (105).
In one embodiment of the present invention, the purity of the 3'-(Trifluoromethyl) acetophenone (TFMAP) obtained by said process (300) maybe in between 99-99.9 %, and % yield maybe in between 60-90% and specifically 70-86%.
The following experiments further illustrate the invention. All parts and percentages are by weight unless explicitly stated otherwise.
EXAMPLES
Example 1: Preparation of Diazo solution

Introducing sulfuric acid in the first reactor containing with constant stirring, followed by addition of 500g 3-aminobenzotrifluoride (an exothermic reaction) to obtain reaction mass. The reaction mass is cooled to 0-2 °C. Further, 135g toluene is added in the reaction mass, followed by slow addition of sodium nitrite solution (225.6g dissolved in 341.6g water) over the course of 2-2.5 hours with constant stirring at temperature of 0-2 °C. After stirring the reaction mass for 30 mins., 17.5g sulfamic acid dissolved in 92.5g water is incorporated to obtain diazo solution.
Example 2: Preparation of 3'-(Trifluoromethyl)acetophenone oxime
Introducing 730g water, 46 gm copper (II) sulfate, 62 gm glacial acetic acid, 930 gm toluene in the second reactor with constant stirring, followed by lot-wise addition of 295g acetaldoxime (50% solution in water) 25% quantity of Diazo solution by maintaining temperature 0-2 °C and pH at 2 to 2.5. After addition of Diazo solution, the pH is raised to 3-3.5, followed by addition of 73g acetaldoxime (50% solution in water) and 25% quantity of Diazo solution twice. In the next step, more 110g acetaldoxime is added along with 25% of diazo solution with constant stirring of 1hr. The temperature is raised till 35-40 °C in subsequent step to separate aqueous layer from organic layer. Further, the aqueous layer is transferred to effluent treatment plant, while the organic layer is washed with 40g of 30% HCl solution to obtain 3'-(Trifluoromethyl)acetophenone oxime.
Example 3: Preparation of crude 3'-(Trifluoromethyl) acetophenone (TFMAP)
Introducing 3'-(Trifluoromethyl) acetophenone oxime into the third reactor, followed by addition of 637g of 30% hydrochloric acid with constant stirring to obtain reaction mass. The reaction mass is heated to 90-95 °C for 5-6 hrs, followed by cooling to room temperature to obtain aqueous and organic layer. The aqueous layer is transferred to effluent treatment plant and the organic layer is washed with 125g of water and 227g 3% sodium hydroxide to obtain 86% of crude 3'-(Trifluoromethyl) acetophenone.
Example 4: Distillation of crude 3'-(Trifluoromethyl) acetophenone (TFMAP) into refined 3'-(Trifluoromethyl) acetophenone (TFMAP)
Transferring the crude 3'-(Trifluoromethyl) acetophenone in toluene to the distillation unit (packed column) to separate hydrolyzed product such as benzotrifluoride from toluene and obtain refined 3'-(Trifluoromethyl) acetophenone (TFMAP).
Example 5: Effluent plant treatment (ETP)
The aqueous effluent layer is transferred to effluent treatment plant (112) as an effluent and treated for and additional recovery 3'-(Trifluoromethyl) acetophenone (TFMAP) from the effluent.
In accordance with embodiment of the present disclosure, the system (100) and process (300) of preparing 3'-(Trifluoromethyl) acetophenone (TFMAP) described above have following advantages including but not limited to:
• Reduction in the loss of final product and thereby increasing the final yield of 3'-(Trifluoromethyl) acetophenone (TFMAP).
• Increase in the purity up to 99.9% and yield up to 90% of 3'-(Trifluoromethyl) acetophenone (TFMAP).
• Reduction in time and energy consumption of the overall process of obtaining 3'-(Trifluoromethyl) acetophenone (TFMAP).
• Reduction in loss of reactants and reaction intermediates as these are recycled in the synthesis of 3'-(Trifluoromethyl) acetophenone (TFMAP).
• 20% of capacity increment in TFMAP production
The embodiments, examples and alternatives of the preceding paragraphs or the description and drawings, including any of their various aspects or respective individual features, may be taken independently or in any combination. Features described in connection with one embodiment are applicable to all embodiments, unless such features are incompatible.
Although implementations for a system (100) and process (300) for the preparation of a 3’-(Trifluoromethyl) acetophenone (TFMAP), comprising of have been described in language specific to structural features and/or process, it is to be understood that the appended claims are not necessarily limited to the specific features or process described. Rather, the specific features and process are disclosed as examples of implementations of a system (100) and a process (300) for the preparation of a 3’-(Trifluoromethyl) acetophenone (TFMAP).
,CLAIMS:WE CLAIM:
1. A system (100) for preparation of a 3’-(Trifluoromethyl) acetophenone (TFMAP), comprising of:
a first reactor (104) enabled for the preparation of a diazo solution from reacting 3-aminobenzotrifluoride and sulfuric acid in the presence of toluene and sodium nitrite (NaNO2) solution;
a second reactor (105) enabled for the mixing and lot-wise addition of acetaldoxime solution and the diazo solution, followed by addition of other reactants to obtain an aqueous layer and organic layer i.e., 3’-(Trifluoromethyl)acetophenone oxime;
a third reactor (110) enabled for the hydrolysis reaction of the 3’-(Trifluoromethyl) acetophenone oxime with the 30% HCl to obtain a 3’-(Trifluoromethyl) acetophenone (TFMAP); and
a distillation unit (113) in association with the third reactor (110) configured for obtaining a refined 3'-(Trifluoromethyl) acetophenone (TFMAP).
2. The system (100) as claimed in claim 1, wherein the third reactor (110) is further configured for layer separation of an aqueous effluent layer and crude organic layer of 3'-(Trifluoromethyl) acetophenone (TFMAP).
3. The system (100) as claimed in claim 1, wherein the third reactor (110) is further configured for transferring the aqueous effluent layer to an effluent treatment plant (112) enabled to retrieve additional 3'-(Trifluoromethyl) acetophenone by treating the aqueous layer from the third reactor (105).
4. The system (100) as claimed in claim 1, wherein a tank (111) is configured for alkaline washing of the crude organic layer of 3'-(Trifluoromethyl) acetophenone (TFMAP) from the third reactor (110) by 3-10% NaOH to remove residual acidity and transfer the crude organic layer of TFMAP to distillation unit (113).
5. The system (100) as claimed in claim 1, wherein the other reactants in the second reactor (105) are water, copper (II) sulfate, glacial acetic acid, and toluene.
6. A process (300) for preparing a 3-(Trifluoromethyl) acetophenone (TFMAP), comprises the following steps:
introducing (301) water in a first reactor (104), followed by reacting 3-aminobenzotrifluoride (3-ABTF) with sulfuric acid (H2SO4) in the presence of toluene and sodium nitrite (NaNO2) solution to obtain a reaction mass A;
adding (302) sulfamic acid dissolved in water in the reaction mass A with constant stirring, followed by heating at 7-8 °C to obtain a diazo solution in the first reactor (104);
coupling (303) the diazo solution and acetaldoxime solution in a lot-wise manner in a second reactor (105) with constant stirring for 4-5 hr, followed by incorporation of other reactants to obtain a reaction mass B having an aqueous layer and organic layer of 3’-(Trifluoromethyl)acetophenone oxime;
elevating (304) the temperature up to 35-40 °C to separate the organic layer from the aqueous layer in the reaction mass B, followed by washing the organic layer with 30% hydrochloric acid solution to obtain a 3'-(Trifluoromethyl)acetophenone oxime;
feeding (305) 3'-(Trifluoromethyl) acetophenone oxime in a third reactor (110), followed by addition of 30% hydrochloric acid solution with constant stirring to obtain a crude 3'-(Trifluoromethyl) acetophenone (TFMAP) containing aqueous effluent layer and crude organic layer; and
distilling (307) the crude organic layer of TFMAP in a distillation unit (113) to obtain a refined 3'-(Trifluoromethyl) acetophenone (TFMAP).
7. The process (300) as claimed in claim 6, wherein the process comprises a sub-step of alkali washing (306) the crude organic layer of 3'-(Trifluoromethyl) acetophenone oxime in a tank (111) by 3-10% of NaOH added from tank (106) to remove residual acidity before distillation.
8. The process (300) as claimed in claim 6, wherein the reaction mass A in the first reactor (104) is mixed for a time period of 1-4 hrs with maintained temperature at -5 to 10 °C.
9. The process (300) as claimed in claim 6, wherein at step (302) the sulfamic acid is added to the reaction mass A to decompose excess NaNO2 and to remove NOx.
10. The process (300) as claimed in claim 6, wherein at step of coupling (303) the diazo solution and acetaldoxime solution in the second reactor (105) the temperature is 0-2 °C and pH 2-3.5.
11. The process (300) as claimed in claim 6, wherein the lot wise addition of diazo solution and acetaldoxime solution is subjected for at least 4 times.
12. The process (300) as claimed in claim 11, wherein the acetaldoxime solution is added in 4-5 parts for first lot-wise addition, 1-2 parts in second and third addition, followed by 2-3 parts in fourth addition of the total addition quantity divided in 8-12 parts.
13. The process (300) as claimed in claim 10, wherein for lot wise addition of acetaldoxime pH is adjusted between 2 to 2.5 for first and second lot, and between 3 to 3.5 for third and fourth lot.
14. The process (300) as claimed in claim 10, wherein the pH in the second reactor (105) is maintained by addition of 30% sodium hydroxide.
15. The process (300) as claimed in claim 6, wherein the 30% hydrochloric acid is added in the third reactor (110) at 70-110 °C for 3-7 hours.
16. The process (300) as claimed in claim 6, wherein the aqueous effluent layer is transferred to effluent treatment plant (112) as an effluent and treated for and additional recovery 3'-(Trifluoromethyl) acetophenone (TFMAP) from the effluent.
17. The process (300) as claimed in claim 6, wherein the 3-(Trifluoromethyl) acetophenone (TFMAP) is prepared by a batch process.
18. A 3’-(Trifluoromethyl) acetophenone (TFMAP) product, comprising:
appearance ranging from colourless to orange liquid;
purity in the range of 99-99.9%; and
yield in the range of 60-90%.
Dated this 07th day of February 2023

Priyank Gupta
Agent for the Applicant
IN/PA- 1454