Showing papers on "Carboxylic acid published in 1983"

New and improved methods for the radical decarboxylation of acids

Abstract: Carboxylic acid esters derived from N-hydroxypyridine-2-thione undergo efficient radical chain decarboxylation to the corresponding nor-alkane on treatment with either tri-n-butylstannane or t-butylmercaptan; in the absence of these hydrogen atom donors a smooth decarboxylative rearrangement giving noralkyl 2-pyridyl sulphides is observed.

An NMR relaxation study on the proton transfer in the hydrogen bonded carboxylic acid dimers

Abstract: We have studied the proton spin‐lattice relaxation times (T1) of a series of benzoic acid (BAC) derivatives and decanoic acid (DAC) over a wide range of temperature and analyzed the results in terms of the double proton switching along the hydrogen bonds. The proton T1 in the high temperature region are analyzed using the classical jump model and the barrier heights for the proton transfer are determined. The thermodynamic parameters for the equilibria between the two configurations in the solid state are also determined by the FT–IR measurements. It is shown that the energetics and dynamics of the proton transfer in DAC and the para‐ and meta‐substituted BAC are all similar, but they are very different in the ortho‐substituted ones. It is suggested that the low temperature behavior of the proton T1 of the dimers of carboxylic acid is due to the tunneling and the asymmetry of the potential brings in a small activation energy.

Direct hydrogenation of carboxylic acids to alcohol and esters

Abstract: This invention provides an improved process for direct hydrogenation of a carboxylic acid to its corresponding alcohol with synthesis gas in the presence of a homogeneous catalyst comprising a ruthenium compound and a Lewis Acid metal halide.

beta-Carbolines as benzodiazepine receptor ligands. 1. Synthesis and benzodiazepine receptor interaction of esters of beta-carboline-3-carboxylic acid.

Abstract: Several esters of beta-carboline-3-carboxylic acid were synthesized and tested in respect to their affinity for the benzodiazepine receptor in bovine cortex membranes. Out of these derivatives, the methyl, ethyl, and n-propyl ester were clearly the most potent, while the n-butyl, benzyl, and 3-pyridylmethyl ester were considerably less active. Moreover, several beta-carboline-3-carboxylates with ethanol derivatives as ester alcohol components were all less active than the ethyl or n-propyl ester themselves. It is concluded that the affinity of beta-carboline-3-carboxylates to the benzodiazepine receptor is profoundly dependent on molecular size, as well as hydrophobic and electronic parameters of the ester alcohol component.

Stereochemistry of oxidative addition of an optically active allyl acetate to a palladium(0) complex

Abstract: Addition de l'acetate de α-methylcinnamyle au complexe Pd(dppe) (P(C 6 H 5 ) 3 ). Il y a formation d'un complexe de π-allyl-Pd(II) avec inversion de configuration

Selenosulfonation of acetylenes: preparation of novel β-(phenylseleno)vinyl sulfones and their conversion to acetylenic and β-functionalized sulfones

Abstract: Etude de l'addition 1,2 du p-tolueneselenosulfonate de Se-phenyle sur les ethynyl benzene, decyne-1, butyne-3ol-1 diphenylacetylene et propiolate de methyle

Stabilized polyester-polycarbonate blends and stabilization process therefor

Abstract: Ester-carbonate interchange in blends of aromatic polycarbonates and poly(alkylene dicarboxylates) is inhibited by adding thereto a hydroxy- or amino-substituted carboxylic acid derivative such as methyl salicylate, malic acid, glycine or dibutyl tartrate.

Ionomers having improved low temperature properties

Abstract: Ionomers of ethylene, unsaturated carboxylic acid and softening comonomer, e.g. alkyl acrylate and/or alkyl vinyl ether having improved low temperature properties are obtained by direct or graft copolymerization at a temperature of from about 100° to about 200° C., followed by neutralization of the carboxylic acid groups with metal ions, such ionomers being characterized by a low level of chain branching of up to about 5.5 chain branches/1000 backbone methylene units.

Synthesis of highly lipophilic crown ether carboxylic acids

Abstract: Synthetic routes to eight highly lipophilic crown ether carboxylic acids are described. Structural variations within this series of crown ether carboxylic acids include changes in the crown ether cavity size, the lipophilic group attachment site, and the basicity of the crown ether oxygens.

Detergent additive product

Abstract: A detergent additive product comprising a C 5 -C 18 aliphatic peroxy carboxylic acid bleach precursor in water releasable combination with a non particulate flexible substrate in a weight ratio of precursor to substrate of 30:1 to 1:10. The aliphatic portion of the precursor incorporates a linear chain including and extending from the carbonyl carbon of from 6 to 10 carbon atoms. The product can also include peracetic acid precursors and other compatible organic and inorganic detergent components.

The regiospecific palladium catalysed hydrocarboxylation of alkenes under mild conditions

Abstract: Alkenes react with carbon monoxide, water, oxygen, hydrochloric acid, and palladium and copper chlorides, to give branched chain acids in good yields.

Aqueous pigment dispersion

Abstract: PURPOSE: The titled dispersion having improved dispersibility, dispersion stability, compatibility with water, providing a film with improved corrosion resistance, adhesivity, etc., obtained by using a specific water-soluble copolymer as a dispersant. CONSTITUTION: (A) 3W98pts.wt. lactone or oxy acid condensate-modified (meth) acrylic monomer {e.g., compound shown by the formula I [R 1 is H, or methyl; R 2 is group shown by the formula II (m is 2W8), group shown by the formula III(R 4 is H, or methyl); R 3 is group shown by the formula IV (n is 2W18)], etc.} is copolymerized with (B) 2W97pts.wt. α,β-ethylenic unsaturated nitrogen-containing monomer (e.g., 1-vinyl-pyrrolidone, etc.), (C) 0W20pts.wt. ethylenic unsaturated carboxylic acid (e.g., acrylic acid, etc.), and (D) 0W91pts.wt. α.β-ethylenic unsaturated monomer (e.g., methyl acrylate, etc.) except components A, B, and C, and solubilized to give a water-soluble copolymer. The water soluble copolymer is blended with pigment and an aqueous medium, to give the desired dispersion. COPYRIGHT: (C)1985,JPO&Japio

Glass fiber-reinforced thermoplastic polyester composition

Abstract: A glass fiber-reinforced thermoplastic polyester composition composed of (A) 100 parts by weight of a polyethylene terephthalate resin having an intrinsic viscosity, measured at 35° C. in ortho-chlorophenol, of from 0.4 to 0.9 and comprising at least 80 mole %, based on the total acid component, of terephthalic acid or an ester-forming derivative thereof and at least 80 mole %, based on the total polyol component, of ethylene glycol or an ester-forming derivative thereof. (B) 5 to 200 parts by weight of glass fibers having an average length of at least 0.2 mm, (C) 0.05 to 3 parts by weight of a partially esterified montan wax acid having a neutralization value (NV) and a saponification value (SV) which are in the following relation 50≦NV≦110 (1) 100≦SV≦180 (2) 10≦(SV-NV)≦100 (3) and (D) at least one component selected from the group consisting of (D1) 0.01 to 3 parts by weight of a sodium or potassium salt of a monocarboxylic acid having 2 to 28 carbon atoms and (D2) 0.1 to 10 parts by weight of an ionic copolymer of an α-olefin and an α,β-unsaturated carboxylic acid, said copolymer containing a mono- to tri-valent metal ion.

Process for the production of carboxylic acid esters and/or carboxylic acids

Abstract: Carboxylic acid esters are produced by reacting an unsaturated hydrocarbon, for example an olefin or an alkyne, with carbon monoxide and an alcohol in the presence of a protonic acid and as catalyst (a) at least one of the metals palladium, rhodium, ruthenium, iridium and cobalt, and (b) copper. In a modification of the invention carboxylic acids are produced by omitting the alcohol reactant and replacing it with water in an amount up to 8 mole equivalents based on the unsaturated hydrocarbon and a solvent other than an alcohol, for example tetrahydrofuran.

Thermal aging study of carboxyl‐terminated polybutadiene and poly(butadiene‐acrylonitrile)‐reactive liquid polymers

Abstract: A thermal aging study of carboxyl-terminated polybutadiene (CTB) and poly(butadiene-acrylonitrile) (CTBN) reactive liquid polymers has been conducted at 50°, 75°, 100°, and 125°C. All CTB and CTBNs are stable at 50°C aging. On aging at higher temperatures prior to use, viscosities of CTB and CTBNs increase, and terminal carboxylic acid functional groups start disappearing. Rate of viscosity increase and rate of carboxylic acid functional group disappearance increase with higher aging temperature and also with higher cyano group concentration in the polymers. The major cause of rapid viscosity increase and disappearance of carboxylic acid functional groups seems to be crosslinking between terminal carboxylic acid groups and cyano groups, which form imide structures. Crosslinking among the unsaturation in polybutadiene segments may contribute to the slow, steady viscosity increase. No acid-anhydride formation and decarboxylation reaction, which may also result in viscosity increase and disappearance of carboxylic acid functional groups, are observed during the thermal aging at elevated temperatures.

Polymeric thickeners and coatings containing same

Abstract: This invention relates to a latex thickener which consists essentially of the free radical addition product obtained by the emulsion polymerization of: (a) 3-15 parts styrene; (b) 15-45 parts ethyl acrylate; (c) 30-60 parts of at least one acid having the formula: ##STR1## wherein R 1 and R 2 can be the same or different and are hydrogen or lower alkyl of 1 to about 3 carbons; and (d) 10-25 parts of a mixture of esters; wherein the mixture of esters is the condensation reaction product of reactive amounts of (i) an ethylenically unsaturated cyclic carboxylic acid anhydride containing from 4 to about 8 carbon atoms; and (ii) an ethoxylated alcohol having the general formula: ##STR2## wherein R is from one to three aliphatic radicals of 1 to about 30 carbon atoms each and n is an integer from about 6 to 150; and (iii) a diol containing from about 2 to about 10 carbon atoms. The novel thickeners of this invention are especially useful in increasing the high shear viscosity of latex coating compositions, and especially coating compositions which contain polymeric vesiculated beads as part of the pigmentation.

Orthocarbonsäure-ester mit 2,4,10-Trioxaadamantanstruktur als Carboxylschutzgruppe; Verwendung zur Synthese von substituierten Carbonsäuren mit Hilfe von Grignard-Reagenzien

Abstract: Ortho Esters with 2,4,10-Trioxaadamantane Structure as Carboxyl Protecting Group; Applications in the Synthesis of Substituted Carboxylic Acids by Means of Grignard Reagents The surprising stability of 2,4,10-trioxa-3-adamantyl derivatives 1 against nucleophilic substitution by organomagnesium compounds is discussed and shown to be caused by unfavourable stereoelectronic and steric factors governing the substitution of these cage compounds (Scheme 2). As a consequence, a number of Grignard reagents 2 containing the carboxyl group masked as 2,4,10-trioxa-3-adamantyl group could be prepared and have been reacted in a second step with various electrophiles (cf. Scheme 4). In the products 7–13 and 15b the carboxyl masking group is removed by mild acid hydrolysis and saponification (cf. Scheme 3) to yield the corresponding acids 16a–21a, 22, and 23a. Acids 21a and 23a have been further transformed to give the macrocyclic lactones 24 and 26, isolated from Galbanum oleo-gum-resin, and acid 22 to give 12-methyl-13-tridecanolide (25), isolated from Angelica root oil. In addition 1-bromo-ω-(2,4, 10-trioxa-3-adamantyl)alkanes 1c and 1b have been used to synthesize (±)-methyl recifeiolate (29b) and pure cis-ambrettolic acid ((Z)-32a).

Photoreduction of polymolybdates(VI) in aqueous solutions containing acetic acid

Abstract: Polymolybdates(VI) have been photochemically reduced to Mov in aqueous solutions containing acetic acid. Carbon dioxide, methane, and succinic acid were isolated as decomposition products of the acetic acid but the quantum yield of their formation was ca. 20 times smaller than that of Mov formation. E.s.r, spin-trapping experiments exhibited the presence of spin-adducts of hydroxyl radical as an oxidation product of water. The photoredox reaction of the polymolybdate(VI) with water was a main process. The reaction mechanism discussed is based on the similarity with the photochemistry for an alkylammonium polymolybdate(VI). The photoredox reaction of the polymolybdate(VI) with water or acetic acid proceeds via the photoinduced formation of a charge-transfer complex between the polymolybdate(VI) and acetic acid, which is preceded by the transfer of an acetic acid proton to an oxygen atom at a photoreducible octahedral site in the polymolybdate(VI).

Increasing the flow of fluids through a permeable formation

Abstract: Method for treating a formation, particularly one containing finely divided particulate material, to increase the flow of fluids through the formation wherein there is injected therein an organosilicon compound, preferably in a hydrocarbon carrier liquid, followed by injection of steam containing a compound which contains ammoniacal nitrogen, selected from the group consisting of ammonium hydroxide, ammonium salts of inorganic acids, ammonium salts of carboxylic acids, quaternary ammonium halides, amine or substituted amine hydrochlorides, derivatives of ammonium cyanate, and water-soluble ammonia or ammonium ion precursors selected from the group consisting of amides of carbamic acid and thiocarbamic acid, derivatives of such amides, tertiary carboxylic acid amides and their substituted and alkylated derivatives A preferred nitrogen-containing compound is urea

Polyester type block copolymer composition

Abstract: An improved polyester type block copolymer composition having a rubber-like elasticity, particularly having excellent heat resistance and water resistance, which comprises a polyester type block copolymer produced from a crystalline aromatic polyester and a lactone in melt-admixture with at least one epoxy compound and optionally further with a carboxylic acid compound selected from an ethylene-carboxylic acid copolymer and an aliphatic carboxylic acid metal salt.

Method for preparation of N-phosphonomethylglycine

Abstract: METHOD FOR PREPARATION OF N-PHOSPHONOMETHYLGLYCINE Abstract of the Invention A method for the production of N-phosphonomethylglycine is dis-closed which comprises the steps of: (1) first reacting 2,5-diketopiperazine with p-formaldehyde, then adding substituted phosphorus compound, all in the presence of a low molecular weight carboxylic acid solvent, to form an intermediate bis-phosphonomethyl-2,5-diketopiperazine compound, (2) isolating said intermediate compound, (3) subsequently reacting said intermediate bis-phosphono-methyl-2,5-diketopiperazine compound with a hydrolyzing agent; and, (4) thereafter acidifying said reactants with a mineral acid to form the end product, N-phosphonomethylglycine.