Showing papers on "Transesterification published in 1969"
Patent•
28 Feb 1969
TL;DR: In this paper, an improved process for preparing METAL CHELATES of BKETOESTERS was proposed, where the CHELATE was derived from a VOLATILE ALCOHOL.
Abstract: AN IMPROVED PROCESS FOR PREPARING METAL CHELATES OF BKETOESTERS DERIVED FROM HIGHER ALCOHOLS, GLYCOLS, POLYOLS OR POLYMERS CONTAINING HYDROXYL GROUPS WHICH COMPRISES REACTING A HIGHER ALCOHOL, GLYCOL, POLYOL OR POLYMER CONTAINING HYDROXYL GROUPS WITH A METAL CHELATE OF A B-KETOESTER DERIVED FROM A VOLATILE ALCOHOL, SO THAT A TRANSESTERIFICATION TAKES WITH ELIMINATION OF THE VOLATILE ALCOHOL.
24 citations
TL;DR: Transesterification of amino acid peptide alkyl and fatty acid esters by treatment with anion- exchange resin shows clear signs of degradation in the presence of Na6(CO3)(SO4)2, Na2SO4 and Na2CO3.
Abstract: Transesterification of amino acid peptide alkyl and fatty acid esters by treatment with anion- exchange resin
23 citations
Patent•
05 Mar 1969
TL;DR: In this article, the authors describe the preparation of polyester from tri-(b -carboxyethyl)-isocyanates and hexamethylene glycol in the presence of Sb2O3 and reacting this polyester with N-methyl morpholine, water and a detergent to give a foam which is cured at 105 DEG C.
Abstract: The invention comprises the alkyl esters of di- and tri-(b -carboxyethyl)-isocyanurates. The compounds are prepared by esterification of di- or tri-(b -carboxyethyl)-isocyanurate with the appropriate alcohol, preferably one containing up to 8 carbon atoms, e.g. by heating the reactants in an acid medium. By limiting the amount of alcohol the partial esters may be obtained. The novel esters may be used to prepare polyesters by transesterification with polyhydric alcohols, e.g. ethylene glycol and butanediol. Examples describe the preparation of di- and tri-(b -carbethoxy)-isocyanurates and of a polyester from tri-(b -carbethoxy)-isocyanurate and hexamethylene glycol. Reference has been directed by the Comptroller to Specification 912,563.ALSO:Polyesters are made by transesterification of alkyl esters of di- or tri-(b -carboxyethyl)-isocyanurate with a polyhydric alcohol. These polyesters react with organic isocyanates to give polyurethanes which may be foamed. Example 3 describes the preparation of a polyester from tri-(b -carbethoxy)-isocyanurate and hexamethylene glycol in the presence of Sb2O3 and reacting this polyester with toluene diisocyanate in the presence of N-methyl morpholine, water and a detergent to give a foam which is cured at 105 DEG C. Reference has been directed by the Comptroller to Specification 912,563.
11 citations
Patent•
30 Jun 1969TL;DR: In this article, the authors describe the role of a second ALKYL group in the 2 or 3 positions of the PHENYL ring as a stabilizer of organics.
Abstract: ESTERS OF DIPENTAERYTHRITOL OR TRIPENTAERYTHRITOL AND 4-HYDROXY-5-ALKYLPHENYLALKANOIC ACIDS HAVING A SECOND ALKYL GROUP IN THE 2 OR 3 POSITION OF THE PHENYL RING ARE STABILIZERS OF ORGANIC MATERIAL. THE COMPOUNDS ARE OBTAINED THROUGH TRANSESTERIFICATION TECHNIQUES.
10 citations
TL;DR: In this article, it was shown that xanthate reacts with t-amine to give quaternary ammonium salt at room temperature, and dithiol carbonates at elevated temperatures.
Abstract: It was previously reported that xanthate reacted with t-amine to give quaternary ammonium salt at room temperature, and dithiolcarbonates at elevated temperatures. Precise study showed that these reaction products are formed by the following three reactions: the alkylation of t-amine with xanthate affords quaternary ammonium salt and the reaction of xanthate with quaternary ammonium salt yields dithiolcarbonate, while there is transesterification between thiolesters and quaternary ammonium salt. The rate constants and equilibrium constants of these reactions were calculated.
8 citations
Patent•
16 Jan 1969
TL;DR: In this article, a process for the preparation of pure, colorless diphenyl terephthalate is described, which comprises heating a dialkyl terephate with phenyl acetate in the presence of activated carbon to temperatures above 150 DEG C. in an inert atmosphere, then adding a transesterification catalyst, such as a titanic acid ester, to remove the alkyl acetate formed in the reaction and introducing the hot carbon-containing crude ester into a relatively high boiling aromatic hydrocarbon, and crystallizing the product after removing the
Abstract: A process for the preparation of pure, colorless diphenyl terephthalate which comprises heating a dialkyl terephthalate with phenyl acetate in the presence of activated carbon to temperatures above 150 DEG C. in an inert atmosphere, then adding a transesterification catalyst, such as a titanic acid ester, thereto, removing the alkyl acetate formed in the reaction and introducing the hot carbon-containing crude ester into a relatively high boiling aromatic hydrocarbon, such as xylene, also in an inert atmosphere, and crystallizing the product after removing the activated carbon through filtration. Optionally, fresh adsorbent may be added along with the aromatic hydrocarbon prior to crystallization.
5 citations
Patent•
26 Mar 1969
TL;DR: In this article, the authors describe the use of organic phosphites of the formula in which R 1, R 2, R 3 and R 4 which may be the same or different are alkyl, cycloalkyl, 4 1 - hydroxycyclohexyl -4 1 - isopropylidene-bis-(4- diphenylphosphite - cyclohexynyl) and then if necessary affecting transesterification between one mol. of the latter and two mols.
Abstract: 1,146,379. Bis - phosphite esters. MELLEBEZONS. 28 April, 1967 [5 May, 1966], No. 19767/67. Heading C2C. [Also in Divisions C3 and C5] The invention comprises organic phosphites of the formula in which R 1 , R 2 , R 3 and R 4 which may be the same or different are alkyl, cycloalkyl, 4 1 - hydroxycyclohexyl - 4 1 - isopropylidenecyclohexyl, aryl, or alkylaryl radicals. They may be obtained by transesterification between one mole of isopropylidene-bis-(4-hydroxycyclohexyl) and two mols. of triphenyl phosphite so as to form isopropylidene-bis-(4- diphenylphosphite - cyclohexyl) and then if necessary affecting transesterification between one mol. of the latter and from 1 to 4 moles of one or more alkanols, 2,2-dicyclohexanol-propane, cycloalkanols or alkylphenols to replace one or more of the phenyl groups by the desired substituent. Preferred reactants in the second stage are n-butanol, decanol (e.g. as obtained by OXO synthesis), octylphenol, nonylphenol, and dimethylcyclohexanol. The transesterification steps are preferably carried out in the presence of an ionizing catalyst, e.g. an alkali metal or alkaline earth metal hydroxide, carbonate, alcoholate or phenate, a strong mineral acid or a polyvalent metal salt. When triphenyl phosphite is reacted with an equimolar proportion of isopropylidene-bis-(4-hydroxycyclohexyl) in the presence of soda the phosphite of the formula is obtained. On further transesterification a product having a polymeric structure of the type wherein the index n is of indetermined value may be formed and the invention also includes such monomeric and polymeric phosphites as novel products. The products are useful as stabilizers and antioxidants for plastics materials and for lubricants and hydraulic transmission fluids.
3 citations
TL;DR: The conclusion can be reached that k 4 > k 3 (the deacylation rate constant in alcoholysis is larger than the corresponding one in hydrolysis).
3 citations
Patent•
15 May 1969TL;DR: In this article, a transesterification of compounds of formula wherein R is alkyl and one X is H and the other Cl, with glycerol acetonide in the presence of an alkaline substance is described.
Abstract: Novel compounds of formula are prepared by transesterification of compounds of formula wherein R is alkyl and one X is H and the other Cl, with glycerol acetonide in the presence of an alkaline substance. 4 - (21 - Methoxycarbonylphenylamino) - 8 - chloroquinoline is prepared by reaction of 4,8-dichloroquinoline with methylanthranilate. Pharmaceutical compositions in conventional form for oral, rectal or transcutaneous administration comprise an above novel compound and one or more carriers or excipients.
3 citations
TL;DR: Compound I could not be obtained by transesterification of N -acetyl- L -glutamic acid 5-methyl ester with dimethylaminoethanol, whereas L -pyroglutamicacid acid salt (III) was obtained from L - glutamic Acid 5- methyl ester and dimethyaminoeth ethanol.
2 citations
TL;DR: The literature claim that treatment of methyl acrylate with hydrogen bromide in diethyl ether gives methyl 3-bromopropionate exclusively is shown to be erroneous and this transesterification reaction is of value in identifying components of mixtures of fatty esters.
TL;DR: Transesterification of the alkyl esters gives aminoesters of disubstituted glycolic acids in lower yield than reaction of the corresponding acids with halogenoalkylamines as discussed by the authors.
Abstract: Transesterification of ethyl esters of phenyl-2-thiazolyl and phenyl-p-chlorophenylglycolic acid by N-methyl-4-hydroxypiperidine gives N-methyl-4-piperidyl esters of phenyl-2-thiazolyl- and phenyl-p-chlorophenylglycolic acid. Transesterification of the alkyl esters gives aminoesters of disubstituted glycolic acids in lower yield than reaction of the corresponding acids with halogenoalkylamines.
Patent•
23 Sep 1969
TL;DR: In this article, a continuous production of axerophthyl acetate with a lower alcohol using guanidine as transesterification catalyst in two stages, alkyl acetate and some of the excess alcohol being distilled off in the first stage and the remainder of the alcohol being removed in the second stage by distillation with a hydrocarbon as entrainer.
Abstract: Continuous production of axerophthol by reaction of axerophthyl acetate with a lower alcohol using guanidine as transesterification catalyst in two stages, alkyl acetate and some of the excess alcohol being distilled off in the first stage and the remainder of the alcohol being removed in the second stage by distillation with a hydrocarbon as entrainer.
TL;DR: In this paper, the IR spectra of methyl[N-alky(aryl)aminomethyl]-diethoxysilanes with furfuryl and tetrahydrofurfuryls alcohols are given.
Abstract: Transesterification of methyl[N-alky(aryl)aminomethyl]-diethoxysilanes with furfuryl and tetrahydrofurfuryl alcohols gives four new substituted furfuryloxysilanes and three new substituted tetrahydrofur-furyloxysilanes, with a secondary or tertiary amino group in the organic group. Some of the physical properties, as well as the IR spectra of the compounds, are given.
TL;DR: In this article, two means of preparing bis(2-carballyloxyalkyl)dialkylstannanes have been worked out: addition of dialkyltia dihydrides to allyl acrylate or methacrylate; and transesterification of the addition products of Dialkyltin di hydrides with allyl alcohol.
Abstract: 1.
Two means of preparing bis(2-carballyloxyalkyl)dialkylstannanes have been worked out: addition of dialkyltia dihydrides to allyl acrylate or methacrylate; and transesterification of the addition products of dialkyltin dihydrides to methyl acrylate or methacrylate with allyl alcohol.
2.
Some bis(2-carballyloxyalkyl)dialkylstannanes not previously described in the literature have been prepared and studied.