- Synthetic process for antioxidant 1024
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The invention provides a synthetic method for an organic synthesis antioxidant 1024, that is, a synthetic method for N,N'-bis[beta(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl]hydrazine. The preparation method comprises the following steps: firstly synthesizing beta-(3,5-di-tert-butyl-4-hydroxyphenyl)propanohydrazide by using hydrazine hydrate and beta-(3,5-di-tert-butyl-4-hydroxyphenyl)methyl propionate as raw materials, and synthesizing the N,N'-bis[beta(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl]hydrazine by using the beta-(3,5-di-tert-butyl-4-hydroxyphenyl)propanohydrazide and ethyl acetoacetate as raw materials. According to the method provided by the invention, a solvent type, a mass ratio of one reactant to another reactant and a mass volume ratio of reactants to solvents in a reaction system are adjusted, so that the reaction is performed more thoroughly, a product yield is greatly improved, and the product yield in a pilot plant test can still be guaranteed to be higher than acurrent level.
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Paragraph 0038; 0039; 0047; 0048; 0056; 0057; 0063; 0064
(2018/09/21)
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- A process for the preparation of hindered phenol antioxidant
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The invention relates to a novel preparation method for a hindered phenol antioxidant. The problems of multiple reaction steps, lower product yield, high environmental protection pressure and the like in the prior art are solved. According to the method, ester with a hindered phenol structure and hydrazine hydrate or diamine such as ethylenediamine, 1,3-propanediamine, 1,4-butanediamine, pentamethylenediamine or hexanediamine serve as raw materials, a one-step method is adopted for synthesizing a target product, and an alkaline catalyst is added to facilitate reaction. The product is widely applied to electric wires, cables and products embedded with metal parts.
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Paragraph 0028; 0029
(2017/03/17)
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- A method for preparing an antioxidant
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The invention provides a preparation method for an antioxidant. The method includes: subjecting a compound shown as formula (III) and a compound shown s formula (IV) to dehydration reaction in the presence of an organic solvent. The method is characterized in that in the dehydration reaction process, the reaction generated water and part of the organic solvent are separated from the reaction system, and water division treatment is carried out, then the water-containing organic solvent subjected to water division treatment contacts a first dehydrating agent, and the organic solvent obtained after contact is returned to the reaction system. Specifically, n is 1 or 2, x is 1 or 2, y is an integer of 0-6, R1 and R2 are not a straight chain or branched chain alkyl group with a hydrogen atom or carbon atom number of 1-6 at the same time, and R3 and R4 are not a straight chain or branched chain alkyl group with a hydrogen atom or carbon atom number of 1-6 at the same time. By adopting the method provided by the invention to prepare the antioxidant, the dehydration effect of the reaction system can be enhanced, and accordingly the reaction efficiency and product yield can be enhanced. (formula III and formula IV).
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Paragraph 0064; 0067-0068
(2018/02/04)
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- Process for the preparation of symmetrical diacylhydrazines
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Process for the preparation of symmetrical diacylhydrazines having general formula (I): R1—CO—NH—NH—CO—R1wherein R1represents a linear or branched C1-C18alkyl group; a linear or branched C2-C8alkoxyalkyl group; a C2-C8cyanoalkyl group; a C5-C8cycloalkyl group, said cycloalkyl group optionally containing a heteroatom selected from oxygen, nitrogen and sulfur; a C6-C18aryl group; a C7C20arylalkyl group or alkylaryl group, said arylalkyl or alkylaryl groups optionally substituted with one or more hydroxyl groups, or with one or more linear or branched C1-C8alkoxyl groups; comprising: (a) reacting an ester of a carboxylic acid having general formula (II): R1—CO—OR2wherein R1has the same meanings defined above and R2represents a linear or branched C1-C18alkyl group, with hydrazine, in its pure or hydrated state, obtaining a monoacylhydrazine having general formula (III): R1—CO—NH—NH2; (b) reacting the monoacylhydrazine having general formula (III) obtained in step (a), with a β-ketoester having general formula (IV): R3—CO—CH2—COOR4wherein R3represents a linear or branched C1-C18alkyl group, or a C6-C18aryl group and R4represents a linear or branched C1-C18alkyl group, obtaining the desired symmetrical diacylhydrazine having general formula (I).
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- Synthesis and chemical transformations of β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic hydrazide
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A method for synthesis of β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic hydrazide. Certain chemical properties of the product were studied. It was found that β-(3,5-di-ter-butyl-4-hydroxyphenyl)-propionic β-(3,5-di-tert-butl-4-hydroxyphenyl)hydrazide is highly susceptible to oxidation.
- Ismagilov,Moskva,Lebedev,Mosunova
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p. 931 - 933
(2007/10/03)
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- Synthesis and ESR study of Co and Ni hydrazides and hydroxamates containing 2,6-di-tert-butylphenol moiety in the ligands
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A series of Co and Ni hydrazides and hydroxamates containing the 2,6-di-tert-butylphenol moiety as a potential free radical precursor in the ligand environment of the complexes were synthesized.ESR spectroscopy was used to study the dependence of the stability of metal complexes incorporating a parametric center in the ligand on the type of the coordination environment of the metal and the nature of the ligand.The complexes, in which a saturated aliphatic bridging group separates the 2,6-di-tert-butylphenol moiety and the coordination environment of the metal, can undergo oxidation to produce stable paramagnetic species with an unpaired electron in the ligand environment.The interation of the free radical center in the ligand with the coordination environment of the metal is practically absent (excepting the weak spin-spin interaction).Metal complexes incorporating a hydrazine moiety conjugated with the 2,6-di-tert-butylphenol substituent do not produce detectable stable paramagnetic forms with a free radical in the ligand. - Key words: hydrazides, hydroxamates, metal complexes; paramagnetic ligands, ESR spectroscopy.
- Zav'yalov, I. A.,Polyakova, O. V.,Milaeva, E. R.,Prokof'ev, A. I.
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p. 1725 - 1728
(2007/10/03)
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- Synthesis of 2,6-di-tert-butylphenols linked to 1,3,4-oxadiazoles and 1,3,4-thiadiazoles
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The preparation of a series of analogs of 2,6-di-tert-butylphenol linked to a 1,3,4-oxadiazole or 1,3,4-thiadiazole via an ethylene or methyleneoxy spacer is discussed.
- Kramer,Boschelli,Connor
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p. 1439 - 1443
(2007/10/02)
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- 3,5-DITERTIARYBUTYL-4-HYDROXYPHENYL, 1,3,4-THIADIAZOLES AND OXADIAZOLES LINKED BY CARBON, OXYGEN, AND SULFUR RESIDUES
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The novel 3,5-ditertiarybutyl-4-hydroxyphenylthio-1,3,4-thiadiazoles and oxadiazoles and 3,5-ditertiarybutyl-4-hydroxyphenylmethanone-l,3,4-thiadiazoles and oxadiazoles and related compounds of the present invention are antiinflammatory agents having activity as inhibitors of 5-lipoxygenase, cyclooxygenase or both
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- Hindered phenol hydrazones and compositions stabilized therewith
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Hindered phenol hydrazones of the formula STR1 wherein R1 and R2 are alkyl of 1 to 8 carbons or R1 can also be hydrogen, n is 1 to 6, R' is hydrogen or alkyl, R3 is alkyl, phenyl, substituted phenyl, alkylenethioalkyl or alkylenethioether ester of a carboxylic acid or a group STR2 where T is a direct bond, alkylene, sulfur or oxygen interrupted alkylene or phenylene, said compounds being useful as diene rubber stabilizers.
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