- Synthesis of Fatty Alcohol based Sterically Hindered Esters as Potential Antioxidants for Bioadditives
-
Abstract: Four hindered phenolic esters were prepared by esterification between 3-(3,5-Di-tert-butyl-hydroxyphenyl)propionic acid and fatty alcohols. The synthesized esters were characterised by NMR, IR and ESI-MS and analysed for their antioxidant proper
- Madhu, Devarapaga,Padmaja, Korlipara V.,Venkateshwarlu, Kontham
-
p. 1309 - 1316
(2020/12/02)
-
- Synthesis process of antioxidant 1076
-
The invention provides a method of organically synthesizing an antioxidant 1076, i.e. octadecyl 3-(3,5-ditert-butyl-4-hydroxyphenyl)propionate. The preparation method comprises the following steps: bytaking a mixed solution of ethylene glycol and methylbenzene as a solvent, and by taking methyl 3-(3,5-ditert-butyl-4-hydroxyphenyl)propionate and stearyl alcohol as reactants, adding a catalyst andreacting to obtain the octadecyl 3-(3,5-ditert-butyl-4-hydroxyphenyl)propionate. According to the preparation method, the mixed solution is used as the solvent, and the catalyst is added in batches ina reaction process, so that the organic synthesis method provided by the invention has the advantages that in the reaction of preparing the octadecyl 3-(3,5-ditert-butyl-4-hydroxyphenyl)propionate, the use amount of the catalyst is less, the reaction temperature is low, the obtained product is high in purity, and the yield is still up to 92 percent or above in pilot scale test.
- -
-
Paragraph 0012; 0050-0120; 0122
(2018/09/08)
-
- Method for preparing n-Octadecyl-beta-(4-hydroxy-3,5-di-tert-butyl-phenyl)-propionate at high pressure
-
The invention relates to a method for preparing n-Octadecyl-beta-(4-hydroxy-3,5-di-tert-butyl-phenyl)-propionate at high pressure. The adopted technical scheme is that the method comprises the following steps of taking beta-(3,5-di-tert-butyl-4-hydroxyphenyl) methyl propionate, octadecanol, a catalyst and solvent, and enabling the substances to react at the pressure of 2 to 3MPa and the temperature of 110 to 120DEG C for 6 to 7 hours, thus obtaining the beta-(4-hydroxy-3,5-di-tert-butyl-phenyl)-propionate. The method disclosed by the invention is simple and is low in energy consumption, and wastes are utilized; the purity of the obtained n-Octadecyl-beta-(4-hydroxy-3,5-di-tert -butyl-phenyl)-propionate is high.
- -
-
Paragraph 0017-0028
(2017/02/17)
-
- METHODS AND COMPOSITIONS FOR INHIBITING VINYL AROMATIC MONOMER POLYMERIZATION
-
Methods and compositions are provided for inhibiting the polymerization of a vinyl aromatic monomer, such as styrene monomer, during elevated temperature processing thereof or during storage or shipment of polymer containing product. The compositions comprise a combination of a quinone methide derivative A) and a phenol compound B). The methods comprise adding from about 1-10,000 ppm of the combination to the monomer containing medium, per one million parts of the monomer.
- -
-
-
- Method for making hindered phenolic antioxidant
-
A method for making a hindered phenolic antioxidant based on Octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate uses a methanol solution containing alkali metal methoxide as a catalyst solution, wherein the catalyst solution is filtered with a filter device with a filter pore diameter of less than 50 μm to remove insoluble matters therefrom before used in a transesterification process where methyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate and 1-Octadecanol are taken as reactants to obtain a crude product of Octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate having high conversion rate and low color, and the crude product further undergoes a purification process for crystallization, filtering and drying to obtain a product of Octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate having high purity and low color.
- -
-
Page/Page column 3-4
(2010/08/22)
-
- Nucleophilic acyl substitutions of esters with protic nucleophiles mediated by amphoteric, oxotitanium, and vanadyl species
-
(Chemical Equation Presented) A diverse array of oxometallic species were examined as catalysts in nucleophilic acyl substitution (NAS) reactions of methyl (or ethyl) esters with protic nucleophiles. Among them, oxotitanium acetylacetonate (TiO(acac)2) and vanadyl chloride (VOCl 2-(THF)x) served as the most efficient and water-tolerant catalysts. Transesterifications of methyl and/or ethyl esters with functionalized (including acid- or base-sensitive) 1° and 2° alcohols can be carried out chemoselectively in refluxed toluene or xylene in a 1:1 substrate stoichiometry using 1 mol % catalyst loading. The resultant products were furnished in 85-100% yields by simple aqueous workup to remove water-soluble catalysts. The new NAS protocol is also amenable to amines and thiols in 74-91% yields, albeit with higher loading (2.5 equiv) of protic nucleophiles. Representative examples of commercial interests such as Padimate O and antioxidant additives for plastics were also examined to demonstrate their practical applications. A 1:1 adduct between TiO(acac)2 and a given 1-octadecanol was identified as (C18H37O) 2Ti(acac)2 and was responsible for its subsequent NAS of methyl esters.
- Chen, Chien-Tien,Kuo, Jen-Huang,Ku, Cheng-Hsiu,Weng, Shiue-Shien,Liu, Cheng-Yuan
-
p. 1328 - 1339
(2007/10/03)
-
- Mixture of substances containing compounds with vinyl groups and stabilizers
-
A mixture contains one or more vinyl-containing compounds as component (A) and, as a further component, a stabilizer (B) which contains one or more readily volatile nitroxyl compounds as component (b1), one or more sparingly volatile nitroxyl compounds as component (b2), if required one or more aromatic nitro compounds as component (b3) and, if required, one or more iron compounds as component (b4).Stabilizers (B) contain the components (b1) and (b2), (b1) and (b2) and (b3), (b1) and (b2) and (b4), and (b1), (b2), (b3) and (b4), and the premature polymerization of vinyl-containing compounds during their purification or distillation is inhibited by a process in which a stabilizer (B) is added or the components of stabilizer (B) are added as individual substances or in at least two groups of the components.
- -
-
-
- Preparation of substituted hydroxyhydrocinnamate esters by continuous transesterification using reactive distillation
-
Substituted hydroxyhydrocinnamate esters of the formula (I) where R is alkyl, n is 0 to 2, m is 1 to 4 and A is alkyl, interrupted or uninterrupted alkylene, alkanetriyl or pentaerythrityl, are prepared by continuous transesterification of the corresponding lower alkyl mono-ester with an alkanol or polyol of the formula A-(OH)m. This novel process comprises continuously introducing into and reacting the reactants in a heated distillation column reactor having a reaction zone which contains a solid, heterogeneous transesterification catalyst to form the compound of formula (I) and the corresponding lower alkanol; separating the products so formed based on their difference in volatility; and continuously removing said products from the distillation column at a steady rate, thereby preventing the reaction mixture from reaching chemical equilibrium. The continuous reaction results in improved product throughput and product quality and has a lower residence time, as compared to known batch-type processes.
- -
-
-
- Process for the preparation of substituted hydroxyhydrocinnamate esters
-
The transesterification of substituted lower alkyl hydroxyhydrocinnamates with a higher alcohol or a polyol is greatly facilitated by the use of a trace amount of a tin catalyst. In many cases, the amount of the catalyst is so small that it is unnecessary to remove it from the final product by distillation of said product.
- -
-
-
- 4-acylaminopiperidin-N-oxyle
-
4-Acylaminopiperidine N-oxides Ia where A1 is hydrogen or an organic radical and B1 is a radical IIa STR1 where R1 -R4 are each C1 -C4 -alkyl and R1 and R2, on the one hand, and R3 and R4, on the other hand, may furthermore be bonded to form a 5-membered or 6-membered ring, R5 is H or C1 14 C4 -alkyl and R6 is H or C1 -C18 -alkyl, are used for stabilizing organic materials against the harmful effect of free radicals, particularly in the distillation of monomers which undergo free radical polymerization, especially styrene.
- -
-
-
- Process for preparing organic esters and amides and catalyst system therefor
-
Disclosed is a process for the preparation of organic esters and amides by reacting (a) a 5 to 60 mole % excess of an ester of (substituted-4-hydroxyphenyl) alkanoic acid with (b) (i) a C4 -C20 aliphatic alcohol or thioether alcohol having one or more hydroxyl groups or (ii) an amine of the formula, (R"')2 N(CH2)n R"" wherein R"' is hydrogen, C1-7 alkyl, C5-12 cycloalkyl, or C6-12 aryl, provided that one R"' is hydrogen, and R"" is hydrogen or N(R"')2 wherein R"' is a defined above, in the presence of a catalyst system comprising a basic inorganic compound and a polar aprotic organic compound. The process provides higher yields of the desired product, shorter reaction times, and reduces the production of undesirable side-products.
- -
-
-
- Process for the production of ester compounds
-
In producing ester compound useful as an antioxidant for organic materials which are represented by the formula: STR1 wherein R1 and R2 are the same or different and represent hydrogen or straight or branched chain alkyl radicals containing 1-8 carbon atoms, Z is an organic radical derived from an n-hydroxy alcohol, and n denotes an integer of 1 to 4, by transesterification, monoalkyltin compounds are used as a catalyst, whereby the ester compounds can be produced with high quality and in high yields.
- -
-
-
- Methods and compositions for inhibiting styrene polymerization
-
Methods and compositions are provided for inhibiting the polymerization of styrene monomer during elevated temperature processing thereof or during storage or shipment of styrene containing product. The compositions comprise a combination of (a) a phenylenediamine compound having at least one N-H bond and (b) a hindered phenol compound. The methods comprise adding from 1-10,000 ppm of the combination to the styrene medium, per one million parts of styrene.
- -
-
-
- Organothioethyl alcohol segmers as antidegradant synergists
-
This invention is concerned with the stabilization of organic materials subject to oxidative degradation. The synergists of this invention possess organothioethyl alcohol segmers or moieties which enhance the antioxidative activity of phenolic and amine stabilizers. The invention is also concerned with compounds that contain an organothioethyl alcohol moiety and their use in oxidizable materials in combination with polymerizable and/or conventional antidegradants.
- -
-
-
- Process for the preparation of sterically hindered hydroxyphenylcarboxylic acid esters
-
If the transesterification of esters of formula II STR1 with alcohols of formula III A--OH)m is catalysed by treatment with catalytic amounts of an organic or inorganic zinc salt and the resultant melt is subsequently distilled in a short-time distillation apparatus under specific conditions, then compounds of the formula STR2 are obtained in virtually quantitative yield, in which formulae I, II and III n is a number from 0 to 2, m is 1 or 2, A is a radical derived from an m-valent aliphatic alcohol, which radical contains 2 to 18 carbon atoms, B is methyl or tert-butyl and R is methyl or ethyl. The products thus obtained contain no troublesome by-products and do not have to be additionally purified.
- -
-
-
- Process for the preparation of sterically hindered hydroxyphenylcarboxylic acid esters
-
If the transesterification of esters of the formula II STR1 with alcohols of the formula III STR2 is catalyzed by treatment with catalytic amounts of an oxide or an organo-metallic compound of a metal of the fourth main group or subgroup of the periodic system, and if the resulting melt is then distilled in a flash distillation apparatus under specific conditions, compounds of the formula STR3 are obtained in a virtually quantitative yield. In the above formulae, R is methyl or ethyl, A is a radical of an m-hydric aliphatic alcohol, E is methyl or tert-butyl, m is 1 to 4 and n is 0 to 2. The products thus obtained do not contain any interfering by-products and do not have to be additionally purified.
- -
-
-
- Polymerizable thioester synergists
-
There are disclosed polymerizable thioester synergists which have utility in enhancing the antioxidative activity of phenolic and amine stabilizers. The invention is also concerned with the thioesters themselves, their use in oxidizable organics, their combination with polymerizable and/or conventional antioxidants, and with polymers which contain these thioesters as physical admixtures or segmeric units of the polymer.
- -
-
-
- Compositions containing antimicorbial agents in combination with stabilizers
-
Composition of an antimicrobial agent and an antioxidant having improved antimicrobial activity compared to the antimicrobial agent alone. The preferred environment of the invention is a composition of a thermoplastic resin, an antioxidant, and an antimicrobial agent, the latter two being compatible with the resin. The resin composition can contain other usual additives, and can be melt processed at an elevated temperature to form articles such as films or fibers having improved antimicrobial activity. A method for improving the efficacy of an antimicrobial agent by combining it with an antioxidant is disclosed. A method for melt-processing a resin composition containing an antimicrobial material is also disclosed, wherein the resin composition includes an antioxidant. The inventors have thus discovered and solved the problem of oxidation of an antimicrobial composition, particularly a resin composition containing an antimicrobial agent, which arises when the composition is processed at elevated temperatures, as are typically encountered when forming a fiber or film of the composition.
- -
-
-
- Process for the preparation of sterically hindered hydroxphenylcarboxylic acid esters
-
If the transesterification of esters of the formula STR1 with alcohols of the formula III A--(OH)m is catalyzed by successive treatment with catalytic amounts (a) of a tin compound of a metal of the fourth main group or the fourth sub-group of the periodic system and (b) of an acid earth, compounds of the formula I STR2 are obtained in virtually quantitative yield. The products thus obtained contain no troublesome by-products and do not have to be additionally purified. R is methyl or ethyl, A is a radical derived from an m-hydric aliphatic alcohol, n is 0 to 2, and m is 1 to 4.
- -
-
-
- Synergistic antioxidant mixtures
-
Compounds prepared by reacting maleic anhydride, maleic acid or their esters with thiols; which exhibit a synergistic effect when combined with a phenolic antioxidant in the stabilization of organic materials such as natural and synthetic polymers, rubbers, lubricants and oil, etc. are disclosed.
- -
-
-
- Isocyanuric acid ester stabilizer
-
An isocyanuric acid derivative useful as a stabilizer for organic substances, which is represented by the general formula STR1 wherein A represents STR2 R being an alkyl, cycloalkyl, aryl or aralkyl group having 1 to 8 carbon atoms; a process for preparing same; organic substances stabilized with same; and a method of stabilizing an organic substance.
- -
-
-
- Synergistic antioxidant mixtures
-
Compounds of the formula: STR1 wherein R, R' and R2 are alkyl radicals having 1 to 20 carbon atoms, phenyl radicals which may be substituted by 1 or 2 alkyl groups having 1 to 8 carbon atoms, aralkyl radicals having 7 to 12 carbon atoms, or cycloalkyl radicals having 5 to 12 carbon atoms; and wherein R3 is hydrogen or an alkyl radical having from 1 to 4 carbon atoms. These compounds have utility as synergistic stabilizers with phenolic type antioxidants for the stabilization of organic materials such as natural and synthetic polymers, rubbers, lubricants and oils, etc.
- -
-
-
- Synergistic antioxidant mixtures
-
Compounds of the formula: STR1 wherein R is selected from (1) alkyl radicals having 6 to 20 carbon atoms; (2) phenyl radicals which may be substituted by 1 or 2 alkyl groups having 1 to 8 carbon atoms; or (3) aralkyl radicals having 7 to 12 carbon atoms; and wherein R1 is selected from (1) alkylene radicals having 2 to 6 carbon atoms; (2) cycloalkylene radicals having 5 to 12 carbon atoms; (3) alkylcycloalkylene radicals of the formula --R3 --R2 (R4)n, wherein R2 is a cycloalkylene radical having 5 to 12 carbon and R3 and R4 are alkylene radicals having 1 to 6 carbon atoms, and n equals 1 or 0; (4) or a group of the formula --R5 --YR6, wherein R5 and R6 are alkylene radicals having 2 to 6 carbon atoms and Y is oxygen, sulfur, or a 1,4-phenylene radical. These compounds have utility as synergistic stabilizers with phenolic type antioxidants in the stabilization of organic materials such as natural and synthetic polymers, rubbers, lubricants and oils, etc.
- -
-
-
- Process for the production of hydroxyalkylphenyl derivatives
-
An improved process for the production of hydroxyalkylphenyl derivatives, especially esters and amides containing hydroxyalkylphenyl groups is disclosed, which process comprises gradually adding methyl acrylate, in the presence of an alkaline catalyst, to the alkyl substituted phenolic compound, and adding to the resultant reaction mixture a suitable alcohol or amine, optionally in the presence of a second catalyst which is different from the first catalyst. The improved process results in good yields and in a reduction of undesirable by-products while avoiding isolation of the intermediates.
- -
-
-
- Process for the production of hydroxyalkylphenyl derivatives
-
An improved process for the production of hydroxyalkylphenyl derivatives, especially esters containing hydroxyalkylphenyl groups is disclosed, which process comprises gradually adding methyl acrylate, in the presence of an alkaline catalyst, to the alkyl substituted phenolic compound and a suitable alcohol. The improved process results in good yields and in a reduction of undesirable by-products while avoiding isolation of the intermediates.
- -
-
-
- Hindered phenyl phosphites
-
Compounds of the formula STR1 WHEREIN R1 and R2 are independently alkyl or hydrogen, provided only one of R1 and R2 is hydrogen, R3 is --(A)q --COOR4 or CN, where A is alkylene, R4 is alkyl, phenyl or alkyl substituted phenyl, q is 0 or 1, m and n are each 1 or 2, the values of m and n being such that the trivalent state of P is satisfied, R is (a) halogen, (b) hydroxyl, provided that n is 1 when R is hydroxyl, (c) --XR5 wherein X is S or O, and R5 is alkyl, phenyl, alkyl substituted phenyl, or when X is O, R5 is alkanoyl, benzoyl, or alkyl substituted benzoyl, (d) a group of the formula STR2 wherein R6 is phenylene, alkyl substituted phenylene, or alkylene, X is as defined above, and m and n are each 1, (e) a group of the formula STR3 wherein R7 is hydrocarbyldiacyl, R1, R2 and R3 are as defined above, and m is 2 and n is 1, or (f) a group of the formula STR4 wherein R1, R2 and R3 are as defined above, and m and n are each 1, are suitable for stabilizing organic material against thermal, oxidative and ultraviolet light degradation.
- -
-
-
- 4-Hydroxy-3,5-di-alkyl-phenyl-propionic acid composition suitable as lipid lowering and anti-diabetic agents
-
Pharmaceutical compositions acting on the metabolism which contain as active derivatives of the 4-hydroxy-3,5-di-akylphenyl-propionic acid corresponding to the formula I and II EQU1 wherein R1 and R2 which may be identical or different, each stands for an alkylradical having 1 to 8 carbon atoms, R3 stands for an alkylene radical having 2 to 12 carbon atoms, X stands for hydroxy, alkoxy having 1 to 18 carbon atoms, phenalkoxy having 1 to 4 alkyl carbon atoms, cycloalkoxy having 5 to 8 carbon atoms, --NR4 R5 in which R4 stands for an alkyl group having 1 to 18 carbon atoms, R5 stands for a hydrogen atom or R4 and R5 may form with the nitrogen atom a heterocyclic six-membered ring which may carry another hetero atom and n is an integer from 2 to 4 and process for preparing them.
- -
-
-