Showing papers on "Transesterification published in 1970"
TL;DR: In this paper, a tranesterifying reagent used consists of 15% methanolic sodium methoxide solution 0.5 N, 60% petroleum ether and 25% diethyl ether which forms a one phase system at room temperature.
120 citations
TL;DR: Peptidyl transferase, the enzyme which catalyses formation of peptide bonds, can be stimulated by CCA, the 3′-terminus of tRNA, to catalyse also a transesterification reaction involving nucleophilic attack of Met-tRNAfMet by ethanol to yield fMet-ethyl ester.
Abstract: Peptidyl transferase, the enzyme which catalyses formation of peptide bonds, can be stimulated by CCA, the 3′-terminus of tRNA, to catalyse also a transesterification reaction involving nucleophilic attack of Met-tRNAfMet by ethanol to yield fMet-ethyl ester
59 citations
Patent•
20 May 1970
TL;DR: In this paper, the transversal of a DICARBOXYLIC ACID and a DIOL aided by a METAL SALT CATALYST is described.
Abstract: TRANSESTERIFICATION OF ALKYL ESTERS OF A DICARBOXYLIC ACID AND A DIOL AIDED BY A METAL SALT CATALYST WHEREIN THE REACTION MEDIUM IS PASSED THROUGH AN ELONGATED REACTION ZONE IN PLUG-LIKE FLOW (LITTLE BACK-MIXING OF THE REACTION MEDIUM), WHEREIN SOME OF THE TRANSESTERIFICATION PRODUCT IS MAINTAINED PRESENT AT THE INLET END OF THE REACTION ZONE. THEREBY INACTIVATION OF THE CATALYST IS PREVENTED.
21 citations
Patent•
24 Feb 1970
TL;DR: In this article, the authors describe a scenario in which an ALCOHOL with a HYDROGEN ATOM or a METHYL group is drawn off by a TITANIUM PHENOXIDE CATALYST, in the presence of a Titananium Hexide Catalyst and drawing off the ALCHOOL FORMED by AZEOTROPIC DISTILLATION with the LIGHT OF LOWER ESTER.
Abstract: PROCESS FOR THE MANUFACTURE OF ACRYLIC AND METHACRYLIC HIGHER ESTERS OF MAXIMUM PURITY WITH HIGH YIELDS WITHOUT THE FORMATION OF UNDESIRABLE BY-PRODUCTS DIMINISHING THE YIELDS OR POLLUTING THE INTERMEDIATE REACTION PRODUCTS BY TRANSESTERIFICATION OF AN ALCOHOL WITH AN ACRYLATE OR METHACRYLATE OF THE FORMULA CH2=C(-X)-COO-R IN WHICH X IS A HYDROGEN ATOM OR A METHYL GROUP AND R IS AN ALKYL GROUP CONTAINING LESS CARBON ATOMS THAN THE ALCOHOL, IN THE PRESENCE OF A TITANIUM PHENOXIDE CATALYST AND DRAWING OFF THE ALCOHOL FORMED BY AZEOTROPIC DISTILLATION WITH THE LIGHT OF LOWER ESTER.
12 citations
11 citations
Patent•
01 Jul 1970
TL;DR: A process for the preparation of linear SATURATED POLYESTERS of AROMATIC DICCARBOXYLIC ACIDS and SATURated ALIPHATIC OR CYCLOALIPHATEIC DIOLS, USING CARBOXYlic ACID MANGANESE SALTS as TRANSESTERIFICATION CATALYSTs, was described in this article.
Abstract: A PROCESS FOR THE PREPARATION OF LINEAR SATURATED POLYESTERS OF AROMATIC DICARBOXYLIC ACIDS AND SATURATED ALIPHATIC OR CYCLOALIPHATIC DIOLS, USING CARBOXYLIC ACID MANGANESE SALTS AS TRANSESTERIFICATION CATALYSTS, WHICH CONTAIN FROM 3 TO 20 CARBON ATOMS IN THE ANION AND AN EPOXY GROUP. THE SAID POLYESTERS ARE SUITABLE FOR INJECTIONMOULDING PURPOSES.
5 citations
4 citations
Patent•
21 Jan 1970
TL;DR: Aqueous alkyd stoving lacquer is made by condensing a dicarboxylic acid, a polyhydric alcohol with at least three hydroxyl groups, a fatty acid or ester thereof and, optionally, a non-fatty acid to give an alkyl resin of acid number not more than 8.
Abstract: 1,178,490. Aqueous alkyd stoving lacquers. FARBENFABRIKEN BAYER A.G. 21 Dec., 1967 [22 Dec.. 1966], No. 58194/67. Heading C3R. An aqueous stoving lacquer is made by (a) condensing a dicarboxylic acid, a polyhydric alcohol with at least three hydroxyl groups, a fatty acid or ester thereof and, optionally, a non-fatty acid to give an alkyl resin of acid number not more than 8, (b) reacting this alkyd at 100‹ to 160‹ C. with tetrahydrophthalic acid, endomethylene tetrahydrophthalic acid or a homologue of tetrahydrophthalic acid or with an anhydride of such an acid to give a semiester with a total acid number of 40 to 60, (o) neutralizing the semi-ester to a degree of not more than 95% by addition of an amine and (d) diluting the resulting amine salt with water and, optionally, an organic solvent. Suitable components for making the alkyd (a) are: dicarboxylic acids-adipic, phthalic and isophthalic acids; polyhydric alcohols-glycerol, trimethylol propane, pentaerythritol, dipentaerythritol and sorbitol and mixtures thereof with ethylene glycol, diethylene glycol, butanediols and neopentylene glycols; fatty acid components-various drying, semi-drying or non- drying oils, their transesterification products with polyols and fatty acids and their dimers obtainable therefrom, also the fatty acids obtainable from paraffins and a mixture of C 6 to C 12 fatty acids; non-fatty acids-benzoic, tert.-butylbenzoic and resinic acids. The organic solvent used in step (d) may be an ether, ester, ketone, ether-alcohol or keto-alcohol. Coating compositions are made by adding to the alkyd lacquers an aminoplast (e.g. a melamine-formaldehyde condensate), a pigment (e.g. TiO 2 ) and possibly a siccative or defoaming agent.
2 citations
Patent•
06 Aug 1970
TL;DR: In this article, a mixture of bis-(hydroxyalkylene)-terephthalate and oligomers thereof is used to obtain a precondensate, which is then polycondensed and re-esterified in a second reaction zone, with the aid of added glycol.
Abstract: Terephthalic acid is polycondensed, in a first reaction zone, with a mixture of bis-(hydroxyalkylene)-terephthalate and oligomers thereof so as to obtain a precondensate; a part of the precondensate obtained is then polycondensed in known manner; and the remainder of the precondensate is then re-esterified, in a second reaction zone, with the aid of added glycol so as to obtain bis-(hydroxyalkylene)-terephthalate and oligomers thereof; and the mixture obtained is finally recycled to the first reaction zone. This method avoids known disadvantages of direct reaction of terephthalic acid with glycol or transesterification of a terephthalate.
1 citations
Patent•
04 Jun 1970
TL;DR: In this article, the transesterification of diarylesters of terephthalic and/or isophthalic acid with dihydric phenols at 80-220 degrees C, followed by polycondensation at up to 350C under pressure 0.01-4 Torr, characterised in that 0.001-0.2 mol% of diaryloxydiphenylsilanes (with respect to amt of phenol used) are added to the reaction mass before or during transterification or polycondensing.
Abstract: Preparing linear silicon containing polyarylesters Transesterification of diarylesters of of terephthalic and/or isophthalic acid with dihydric phenols in presence of known transesterification catalysts at 80-220 degrees C, followed by polycondensation at up to 350C under pressure 0.01-4 Torr, characterised in that 0.001-0.2 mol% of diaryloxydiphenylsilanes (with respect to amt of phenol used) are added to the reaction mass before or during transesterification or polycondensation. The aryl residue of the diaryl ester and the diaryloxydiphenylsilane may be the same. The dihydric phenol may be 2,2-bis-(4-hydroxyphenyl)-propane. The aryl residue may be phenyl or cresyl. Presence of the diaryloxydiphenylsilane makes removal of any excess of the other reactants from the polyester easier.
1 citations
TL;DR: In this paper, cyclic phosphites were synthesized on the basis of 1,2- and 3,4-mono-and 1 2,2; 3, 4- and 1 2; 5, 6-di-(0-isopropylidine)-D-mannitols and demonstrated the ability of some of the compounds for transesterification by higher alcohols and oxidation to phosphates by oxygen.
Abstract: 1
Cyclic phosphites were synthesized on the basis of 1,2- and 3,4-mono-and 1,2; 3,4- and 1,2; 5, 6-di-(0-isopropylidine)-D-mannitols
2
The ability of some of the compounds for transesterification by higher alcohols and oxidation to phosphates by oxygen was demonstrated
Patent•
21 May 1970
TL;DR: In this article, the ester exchange in the presence of material already ester-exchanged thereby hindering the formation of insoluble, catalytically ineffective metal compounds is investigated.
Abstract: CONTINUOUS TRANSESTERIFICATION OF DIESTERS WITH DIOLS. G5-. especially of dimethyl terephthalate (I) with ethylene glycol (II) in presence of metal salt catalyst using a reactor having at least one open, indirectly heated passage (esp. reactor according to Austrian Pat. 258,580) and in which the cleaved liquid compounds are removed from the reaction zone, characterised by effecting the ester-exchange in the presence of material already ester-exchanged thereby hindering the formation of insoluble, catalytically ineffective metal compounds. Preferably ester-exchanged material is either fed back to the catalyst-addition zone by removing the separation plate on the floor of the first passage of the reactor, or withdrawn through the reactor sump and fed into the floor of the first passage.
Patent•
22 Apr 1970
TL;DR: In this article, Trehalose, raffinose and sucrose esters are prepared by heating trehalose to a temperature of 100 to 170 C with a fatty acid ester which may contain a hydroxy group.
Abstract: 1,188,614. Sugar esters. CASSELLA FARBWERKE MAINKUR AG. 2 Aug., 1968 [4 Aug., 1967], No. 37034/68. Heading C2C. Trehalose, raffinose and sucrose esters are prepared by heating trehalose, raffinose or sucrose to a temperature of 100‹ to 170‹ C. with a fatty acid ester which may contain a hydroxy group, and 0A5 to 20% by wt. of a basic transesterification catalyst referred to the weight of fatty acid ester employed. The alcohol that is liberated is distilled off. The heating is carried out at reduced pressure and in the absence of solvents.
Patent•
15 Jul 1970
TL;DR: Kuhlmann as mentioned in this paper proposed a general process for the preparation of 4-acyloxybutyric acid esters which comprises condensing an ester of a 4-halobutyric acyclic acid with the potassium salt of an organic carboxylic acid by fusion, preferably in the presence of an alkali metal iodide and/or an organic solvent, followed, if desired, by transesterification with an alcohol, e.g., aluminium isopropylate.
Abstract: 1,198,414. 4-Acyloxybutyric acid esters. UGINE KUHLMANN. 13 Jan., 1969 [30 Jan., 1968], No. 1873/69. Heading C2C. The invention comprises esters of the formula in which R is a formyl, propionyl, isovaleryl, acetylsalicyl, phenylacetyl, cinnamoyl or (2- phenyl-2-ethyl) acetyl group and esters of the formula in which R 1 is a methyl, alkyl, benzyl or cyclopentyl group. They may be prepared by a general process for the preparation of 4-acyloxybutyric acid esters which comprises condensing an ester of a 4-halobutyric acid with the potassium salt of an organic carboxylic acid by fusion, preferably in the presence of an alkali metal iodide and/or an organic solvent, followed, if desired, by transesterification with an alcohol in the presence of a catalyst, e.g. aluminium isopropylate. Alkyl 4-chlorobutyrates wherein the alkyl group is methyl, ethyl or benzyl are prepared by reacting γ-butyrolactone with the appropriate alcohol and hydrogen chloride. Cyclopentyl- and alyl-4-chlorobutyrates are prepared by reacting 4-chlorobutyryl chloride with the appropriate alcohol.
Patent•
23 Dec 1970
TL;DR: Anti-foaming products are produced by reacting together in a single stage, without solvent and in the presence of an oxyalkylation and transesterification catalyst, from 5 to 25% by weight of one or more carbohydrates as discussed by the authors.
Abstract: 1,216,987. Anti-foaming products. RAFFINERIE TIRLEMONTOISE. 30 Nov., 1967, No. 54573/67. Addition to 1,160,144. Heading C2C. [Also in Division C5] Anti-foaming products are produced by reacting together in a single stage, without solvent and in the presence of an oxyalkylation and transesterification catalyst, from 5 to 25% by weight of one or more carbohydrates, from 50 to 80% by weight of one or more esters of fatty acids and from 10-40% by weight of one or more alkylene oxides. Examples prepare products from refinery liquors containing sucrose, palm oil and propylene oxide; saccharose as raw sugar, tallow and propylene oxide; molasses, coconut butter and propylene oxide; blackstrap molasses, tallow and propylene oxide; blackstrap molasses, methyl ester of stearic acid and propylene oxide; saccharose, tallow and ethylene oxide; and saccharose palm oil, ethylene oxide and propylene oxide. In each case the mixture is heated in the presence of potassium hydroxide. Reference has been directed by the Comptroller to Specification 1,099,777.