- Method for catalytically synthesizing malathion by one-pot method
-
The invention discloses a method for catalytically synthesizing malathion by one-pot method, and the method comprises the following steps: mixing diethyl maleate, phosphorus pentasulfide and a basic catalyst, adding methanol, carrying out one-pot reaction, and carrying out post-treating after the reaction is ended to obtain the malathion. The synthesis method is simple in reaction, short in reaction time, low in cost and high in product purity, and has important application significance in pesticide production.
- -
-
Paragraph 0036-0054
(2020/08/02)
-
- CATALYZED AND GREEN PROCESS OF MALATHION
-
The present invention relates to an improved synthesis of malathion. The presence of an acid facilitates the reaction between O,O-dimethyldithiophosphoric acid (O,O-DMDTPA) and maleate and leads to excellent product yield in shorter reaction time with fewer impurities.
- -
-
Paragraph 0030-0032
(2020/05/12)
-
- PROCESS FOR THE PREPARATION OF MALATHION AND ITS INTERMEDIATE
-
The present invention relates to the improved process for the preparation of highly pure form of S-[1,2-(dicarbethoxy)-ethyl]O,O-dimethyl phosphorodithioate having formula (I). The compound of formula (I) has adopted name "Malathion". The present invention also relates to the novel process of preparing intermediate O,O- dimethyldithiophosphoric acid of formula (II), which is useful in the preparation of Malathion. The Malathion prepared by the process of this invention is highly storage stable and toxic impurities are much lower than any other commercial preparation available for the pharmaceutical purpose.
- -
-
Page/Page column 10-12
(2009/03/07)
-
- Process for Preparing Malathion for Pharmaceutical Use
-
The present invention provides a process for preparing a highly pure form of malathion having a reduced level of toxic impurities. In addition, the malathion prepared by the process of this invention is storage stable. The level of toxic impurities in the malathion, e.g., isomalathion, O,O,S-trimethyl phosphorodithioate (MeOOSPS), O,O,S-trimethyl phosphorothioate (MeOOSPO), O,S,S-trimethyl phosphorodithioate (MeOSSPO), malaoxon, isomalathion, diethyl fumarate, methyl malathion, dimethyl malathion, O,O-methyl,ethyl-S-(1,2-dicarboethoxy)ethyl-phosphorodithioate are lower than that of any other commercial preparation of malathion that may be used for pharmaceutical purposes.
- -
-
Page/Page column 13
(2008/06/13)
-
- Oil-in-water emulsions
-
The present invention relates to oil-in-water emulsions comprising 0.001-70% by weight, preferably from 0.5 to 45% by weight, of at least one active substance from the class of the phosphates and/or carbamates, from 0.001-20% by weight, preferably from 0.1-10% by weight, of at least one salt of an aryl polyglycol ether phosphate of the formula I STR1 in which each R1, independently of the others, is hydrogen, C1 -C24 -alkyl, C5 -C15 -cycloalkyl, C8 -C24 -aryl or C6 -C24 -alkaryl, R2 is hydrogen, --O--C1 -C24 -alkyl, --O--C5 --C15 -cycloalkyl, --O--C6 -C18 -aryl or A, M is an alkali metal ion, alkaline earth metal ion or ammonium ion of the formula HN(R3)3, where each R3, independently of the others, is hydrogen, C1 -C4 -alkyl, C5 -C15 -cycloalkyl, C6 -C18 -aryl or a group of the formula --(CH2)z --OH in which z is a number from 1 to 10, x is a number from 0 to 80 and y is a number from 0 to 50, the sum of x and y not being zero, and, to make up to 100% by weight, water and, if desired, solvents and/or additives. These oil-in-water emulsions are preferably employed in agriculture and in horticulture, in the domestic and hygiene sectors and/or in the medical sector.
- -
-
-
- Impregnated porous granules and a polyurethane matrix held within the pores thereof and holding a liquid material for controlled release of liquid material and process therefor
-
A composition of matter having a clay porous granule and a polyurethane matrix formed from the polymerization of a polyol and a polyisocyanate and held within the pores of the granule and having uniformly distributed throughout the polyurethane matrix a liquid material, for example, a pesticide and a method for loading a porous granule with the polyurethane and the liquid material by: (a) spraying a porous granule with a liquid composition comprising a polyol, a polyisocyanate and a liquid material to be retained in the porous granule, and (b) polymerizing the polyol and the polyisocyanate to form a polyurethane matrix polymer which has the liquid materials uniformly distributed throughout the polyurethane matrix.
- -
-
-
- Pesticidal composition containing a microencapsulated organo-phosphorus or carbamate in a pyrethroid dispersion
-
An insecticidal and/or acaricidal and/or nematicidal composition having a rapid efficacy and residual activity which comprises a mixture of a poorly water-soluble organophosphorus insecticide and/or acaricide and/or nematicide and/or a poorly water-soluble carbamate insecticide and/or acaricide which have been microencapsulated in water-insoluble polymer coatings with a dispersing agent used in forming a microcapsule part, with a poorly water-soluble pyrethroid insecticide and/or acaricide emulsified or suspended in water with the above-mentioned dispersing agent used in forming a flowable part.
- -
-
-
- Oil-in-water emulsions and a process for their preparation and their use
-
Oil-in-water emulsions (microemulsions) containing 0.01-80% by weight of at least one agrochemical active substance of low water-solubility, one active substance for combating pests in the domestic and hygiene sector and/or one pharmacologically active substance, 1% to 30% by weight of an emulsifier mixture of non, ionic and anionic compounds and at least one alkylarylsulfonic acid salt, as defined in the description, as well as water and, if appropriate, 1% to 30% by weight of at least one solvent of low water-miscibility and/or one solubilizer, and if appropriate 0.05% to 15% by weight of additives, the sum of the components in each case being 100% by weight, a process for the preparation of these aqueous microemulsions and their use.
- -
-
-
- Macrocyclic plant acaricides
-
Compounds of the formula I STR1 in which either R is methyl and there is a double bond in the 9,10-position, or in which R is hydrogen and there is a single bond in the 9,10-position, are highly active against Acarina which damage plants.
- -
-
-
- Biocidal macroemulsions containing polyvinyl alcohol
-
The present invention relates to new macroemulsions which contain 0.001 to 60 percent by weight of at least one active compound from the class comprising the phosphates and/or carbamates, 0 to 50 percent by weight of aromatic diluents, 0.001 to 20 percent by weight of polyvinyl alcohol having a mean molecular weight of between 5,000 and 150,000 and a content of acetate groups of between 2 and 30 mol %, and/or 0.001 to 20 percent by weight of a nonlphenol/propylene oxide/ethylene oxide adduct of the formula STR1 in which X represents integers from 10 to 50 and Y represents integers from 15 to 65, and/or 0.001 to 20 percent by weight of ethylene oxide/propylene oxide/ethylene oxide block copolymers having a mean molecular weight of between 2,000 and 8,000 and HLB values of between 8 and 30, and water and, if appropriate, additives, and in which the oil phase is dispersed in the aqueous phase in the form of droplets having a mean particle diameter of 0.1 to 3.0 μm.
- -
-
-
- Oil-in-water emulsions, and their use
-
Novel oil-in-water emulsions, which contain (a) 0.1 to 80% by weight of at least one sparingly water-soluble active compound (as herein defined) selected from agrochemical active compounds, active compounds for combating pests in the domestic field and hygiene field and/or pharmacologically active compounds, (b) 1 to 20% by weight of at least one alkylaryl polyglycol ether of the general formula STR1 wherein R1 represents a hydrogen atom or an alkyl group having 1 to 16 carbon atoms, R3 represents a hydrogen atom or a methyl group, m is 1, 2 or 3, and n is an integer from 10 to 50, if appropriate in a mixture with an alkylarylsulphonic acid salt of the general formula STR2 wherein R3 represents an alkyl group having 8 to 35 carbon atoms and Me≈ represents an alkali metal cation, an equivalent of an alkaline earth metal cation or a cation of the general formula STR3 wherein R', R", R'" and RIV independently of one another represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms or a hydroxyalkyl group having 1 to 4 carbon atoms, (c) water, (d) if necessary, 1 to 30% by weight of at least one poorly water-miscible organic solvent and/or a solubilizer, and (e) if appropriate 0.05 to 15% by weight of one or more additives, the sum of the components being 100% by weight in each case, a process for the preparation of these emulsions and their use in the field appropriate to the active compound.
- -
-
-
- Process for the preparation of malathion
-
Process for the preparation of malathion by reacting O,O-dimethyl-dithiophosphoric acid with ethyl maleate in the presence of a solvent which forms a heterogeneous azeotrope with the O,O-dimethyl-dithiophosphoric acid.
- -
-
-