FORM-2
THE PATENTS ACT, 1970
COMPLETE
SPECIFICATION
SECTION 10
TITLE : A PROCESS FOR PREPARING PRALLETHRIN
APPLICANT (S): SHOGUN ORGANICS LIMITED, 504, SAMARTHA VAIBHAV,
LOKHANDWALA COMPLEX, OFFLEMK ROAD, ANDHERI (W), MUMBAI 400 053, MAHARASHTRA, INDIA.
The following Specification particularly describes the nature of this invention and the
manner in which it is to be performed.

FIELD OF THE INVENTION
This invention relates to method for repelling insects and further relates to Process synthesis of manufacture of "Prallethrin" technical. The product is used as an active ingredient in mosquito repellant and control products. The process includes the esterification of an optically active alcohol with an acid chloride. The ester so formed has high insect repellant properties. This special synthesis route has been developed for specific use in household insecticide products as an active ingredient against mosquitoes.
BACK GROUND OF THE INVENTION
Harmful insects can carry agents that cause disease. For example, mosquitoes can carry viruses that cause encephalitis. Ticks can carry bacteria that cause Lyme disease. Furthermore, insect bites, such as mosquito or fleabites, can be an annoyance. Therefore, it is an object of this invention to provide a device that prevents insects from landing on a user of the device, thereby defending the user from suffering insects bites and insect landings. It is a further object of this invention to provide personal protection devices that repel insects, particularly mosquitoes.
TOPICAL REPELLENTS
Topical repellents contain relatively high amounts of insect repellent that can be absorbed into the bloodstream through the skin. Therefore, it is an object of this invention to provide a method for repelling insects using a lower level of insect repellent than that in the topical compositions. Topical repellents also suffer from


the draw back that they only protect the skin to which they are applied. Therefore, if a user does not cover all skin and clothing with a sufficient amount of the topical repellent, the user may suffer insect bites and insect landings in the areas missed when the repellent was applied. It is a further object of this invention to provide a more convenient method for repelling insects than the use of topical repellents.
SUMMARY OF THE INVENTION
This invention relates to methods preparing Prallethrin for repelling insects. The devices each comprise a composition comprising an insect repellent, preferably a pyrethroid such as allethrin. The devices actively disperse the insect repellent in an area (e.g., a scent-stream) around the subject, thereby preventing insects from reaching the subject. Without wishing to be bound by theory, it is thought that insects travel upwind to reach subjects by following scent cues in a 'scent-stream' from the subject. Therefore, it is believed that releasing a composition comprising an insect repellent into the scent-stream insects follow prevents insects from reaching the subject.
The invention relates to process of manufacture a chiral pyrethroid insecticide. It is effective to kill or repel mosquitoes and other insects. It is a yellow to dark brown viscous liquid. The effective synthesis process would give results of minimum 90% pure content. Other related allowed impurities are formed.
Prallethrin is also assumed that its characteristic knockdown and insect toxicity are associated to a greater or lesser degree with certain of the several isomers present. To establish quantitatively their relative insect toxicity, it would be necessary to prepare and test all the optical isomers.


Chrysanthemic Acid Chloride being used for the synthesis of this pyrethroid. This is reacted with alcohol to form an ester. Ester is then separated and distilled to form final prallethrin. Pyridine and toluene are used in the reaction as solvents the stepwise manufacturing process synthesis of prallethrin has been stated.
PROCESS OF MANUFACTURE
Step I: Reaction
Chrysanthemic Acid Chloride (690 gms) and Allethlone Alcohol (.550gms) is reacted with solvent Pyridine (110 ml.) and Toluene (1100 ml) in a reactor for 26 to 30 hours. After reaction is completed, mass is transferred to separating vessel.
Step II: Separation
Physical layer separation. Sodium Bi-carbonate (150 gms ) is added. Aqueous layer is discarded. Organic layer transferred to distillation vessel. This step takes 15 to 18 hours.
Step III: Distillation
Toluene is distilled off under vacuum to obtain prallethrin technical. This step takes 8 to 10 hours.
The synthesized pyrethroid can be used in specific formulations in India as approved by the insecticide registration committee. This can work as an effective solution to mosquito control. The special 3-step process of synthesis of prallethrin technical is highly effective method of manufacture of this high efficacy, low human toxicity product. The chemical synthesis route has been invented by us with complete study on it effects on mosquitoes. Effective isomers are formed which give maximum repellant and knockdown effect to mosquitoes. The synthesis process can be replicated in small laboratory scale experiments as well as large commercial scale production. It gives consistent results.


We Claim:
1. Process of manufacturing a chiral Prallethrin consisting of following steps:
(i) chrystanthemic acid chloride and allethlone alcohol reacted with the
solvents like pyridine to 26 to 30 hours and mass is transferred to
separating vessel,
(ii) sodium bicarbonate is added to the mass organic layer is transferred to distilled vessel,
(iii) organic layer is distilled and vacuum for about 8 to 10 hrs to obtain
parallelthrin at a temerature of ...
2. Organic layer cyliemol in claim- 1 is a toluene.
3. The process of manufacturing chiral Prallethrin as described in claim 1 and
accompanying chemical reaction.


ABSTRACT
This invention relates to method for repelling insects and further relates to Process synthesis of manufacture of "Prallethrin" technical. The product is used as an active ingredient in mosquito repellant and control products. The process includes the esterification of an optically active alcohol with an acid chloride. The ester so formed has high insect repellant properties. This special synthesis route has been developed for specific use in household insecticide products as an active ingredient against mosquitoes.