Abstract: A method for purifying a dimethyl naphthalene dicarboxylate produced from a naphthalene dicarboxylic acid which is in turn produced by the liquid phase oxidation of a dialkylnaphthalene or partially oxidized derivative thereof in the presence of a catalyst comprising a bromine-containing component and at least one of a cobalt- or manganese-containing component.

Abstract: Disclosed are phenyl esters of stilbenedicarboxylic acid. The carboxylate portions of the compounds are bonded at the meta or para positions of the stilbene moiety.

Abstract: The yield of dimethyl terephthalate obtained by the oxidation of a mixture of p-xylene and methyl p-toluate, preferably with air, and esterification of the thus-produced acids is increased by utilizing a mixture of cobalt and manganese compounds as the oxidation catalyst.

Abstract: Disclosed is a process for producing dimethyl or novel diphenyl derivatives of stilbenedicarboxylic acids from dimethyl toluates or diphenyl toluates and sulfur. The reaction requires an excess of toluate to sulfur of at least about 5:1. In addition hydrogen sulfide is removed from the reaction zone.

Abstract: Aryl arylate esters substituted with an acyl moiety on both the aryl and arylate groups of said esters which can be produced by the oxidation of alkyl substituted aryl arylate esters using a heavy metal/bromine catalyst.

Abstract: A block of dimethylterephthalate having a needle-like crystal structure. The block is easily cleavable, and has a reduced tendency to fuse to other blocks when subjected to bag-stacking pressure.

Abstract: Aryl arylate esters substituted with an acyl moiety on both the aryl and arylate groups of said esters which can be produced by the oxidation of alkyl substituted aryl arylate esters using a heavy metal/bromine catalyst.

Abstract: A process for the production of dimethyl terephthalate from p-xylene and methanol by oxidation in a reactor, in the liquid phase with atmospheric oxygen in the presence of dissolved heavy metal compounds as a catalyst, of a mixture of p-xylene and a fraction containing predominantly methyl p-toluate, which fraction is recycled into the oxidation, to obtain an oxidation product containing primarily p-toluic acid and monomethyl terephthalate, at a temperature of 140.degree.-170.degree. C. and under a pressure of 4-8 bar; by esterification of the oxidation product with liquid and subsequently vaporized methanol brought to an elevated pressure, at a temperature of 220.degree.-280.degree. C.

Abstract: Disclosed is a highly efficient continuous method for the aqueous extraction of water-soluble oxidation catalyst material from a residue such as that generated in the production of dimethyl terephthalate from p-xylene by the molecular oxygen oxidation and methanol esterification process. In the method the desired end product is an aqueous solution of the catalyst material. The residue to be extracted is established in finely dispersed condition in part of the aqueous solution at a weight ratio of aqueous solution to residue of above about 1:1 and maintained in that condition for a length of time sufficient for maximum transfer of catalyst material from the residue to the aqueous solution to take place. The resulting dispersion then is separated in a phase separation zone into an aqueous phase and an extracted residue phase. The separated aqueous phase is withdrawn from the phase separation zone as the aqueous solution.

Abstract: A process for the production of a crude dimethyl terephthalate suitable for hydrolyzing into a fiber grade terephthalic acid involves separating a crude ester obtained from the production of dimethyl terephthalate by the Witten process by vacuum distillation at elevated pressure in a three-column series arranged distillation system. In the first distillation column of the system the crude is separated into a methyl p-toluate-rich fraction as head product; in a second column of the series, into a fraction rich in methyl ester of terephthalaldehydic acid as head product; and in a third distillation column, a crude dimethyl terephthalate fraction. The crude dimethyl terephthalate fraction has a methyl ester of terephthalaldehydic acid content of 0.01-0.1% by weight as a head product.

Abstract: A method for preparing a carboxylic ester by reacting an aldehyde with an alcohol in the presence of oxygen with a catalyst, characterized in that the catalyst is a solid catalyst comprising palladium and bismuth, which may form an intermetallic compound, and which catalyst may comprise an alkali metal compound or an alkaline earth metal compound. The aforesaid catalyst avoids decomposition reactions simultaneously with the desired reaction, and therefore, the desired compound can be obtained in a high yield.

Abstract: A process for the recovery and reuse of heavy metal oxidation catalyst from residues in the Witten DMT process by extraction, which involves mixing and settling of the residue with water or dilute aqueous solutions of water-soluble, low-molecular, aliphatic monocarboxylic acids at 70.degree.-160.degree. C. and recycling of the extract of the high-boiling distillation residues into the DMT process. The high-boiling distillation residue and the extractant are used in a quantitative ratio of 1:0.9 to 1:0.1, preferably 1:0.5 to 1:0.3.

Abstract: A process for the recovery and reuse of a heavy-metal oxidation catalyst solution from a high-boiling distillation residue having a cobalt content of 1-10 g/kg of residue is disclosed. The distillation residue is obtained in the production of dimethyl terephthalate by the oxidation of mixtures containing p-xylene and/or methyl p-toluate in the liquid phase with oxygen or an oxygen-containing gas under an elevated pressure and at an elevated temperature in the presence of dissolved heavy-metal oxidation catalyst, by subsequent esterification of the oxidation product with methanol and by a distillatory separation of the esterification product into a fraction rich in methyl p-toluate, a fraction rich in dimethyl terephthalate, and the high-boiling distillation residue.

Abstract: Disclosed is an improvement in the process for making an aromatic carboxylic acid or its methyl ester from an aromatic compound having at least one methyl or formyl group bonded directly to a nuclear carbon atom of the aromatic ring. The process comprises effecting oxidation of said compound in the liquid phase with molecular oxygen or a gas containing the same with a catalyst comprising a heavy metal compound, and in the substantial absence of an aliphatic carboxylic acid as a solvent, whereby a reaction mixture comprising the acid is formed. If the ester is desired, the acid then is esterified with methanol. The improvement comprises carrying out the oxidation in the co-presence of a lithium compound at a concentration of 0.1-10 moles per mole of heavy metal compound. The lithium compound is at least partly soluble in the reaction mixture or reacts with an acid component of the reaction mixture to form a lithium compound soluble in the reaction mixture.

Abstract: Disclosed is a process for converting aromatic aldehydes to the corresponding acid chlorides by reacting an aromatic aldehyde with sulfuryl chloride in the presence of a catalytic amount of a phosphine, phosphine oxide or phosphonium compound. The product compounds produced by the process of this invention are useful as chemical synthesis intermediates in the preparation of pharmaceuticals, dyes, herbicides and photographic chemicals.

Abstract: A process for effecting the recovery and use of a heavy metal oxidation catalyst from a high-boiling distillation residue obtained during the Witten process for the production of dimethyl terephthalate involves the extraction of the high-boiling distillation reside with water or dilute aqueous solution of low molecular weight aliphatic monocarboxylic acids or alcohols and recycling of the extract into the oxidation stage of the Witten process. In the extract the quantitative ratio of the sum of the amount of trimellitic acid and monomethyl ester of trimellitic acid to the amount of heavy metal catalyst is controlled to be at a value of no more than 1.8:1 and in the oxidation stage of the Witten process the catalyst concentration (c), expressed in p.p.m., is represented by the formula:c=44.multidot.(a/b)+dwherein a represents the sum of trimellitic acid and monomethyl ester of trimellitic acid, b is the amount of heavy metal oxidation catalyst within the extract, and d is in a range of from 60 to 300 p.p.m.

Abstract: Malonic anhydride and substituted malonic anhydrides are prepared by ozonolysis of the enol-lactone dimers of ketenes. The resulting malonic anhydrides can be hydrolyzed with water to form the corresponding acid, reacted with an alcohol to yield the monoester, or reacted with an amine to yield the monoamide.

Abstract: Disclosed is an improvement in a method for the recovery for recycle to the cooxidation-coesterification process for the production of dimethyl terephthalate from p-xylene, air and methanol of oxidation catalyst by aqueous extraction of a distillation residue containing the same. To minimize recycle of any iron present in the residue, iron oxidant material (for example, hydrogen peroxide) is admixed in one embodiment with the residue and water in the aqueous extraction procedure, and in a second embodiment with the resulting aqueous extract. In both embodiments, if any iron is present, it is precipitated. In the first embodiment the precipitate stays with the residue. In the second embodiment the aqueous extract is separated from the precipitate.

Abstract: A process for the preparation of dimethyl terephthalate by the oxidation of p-xylene/methyl p-toluate mixtures, preferably with air, esterification of the resulting acid products, and recycling of the methyl p-toluate to the oxidation stage, employs an oxidation catalyst consisting of a combination of cobalt and manganese compounds. The concentration of manganese (Mn.sup.++) ranges between about 0.0001% and about 0.005% by weight.

Abstract: Disclosed is a process for the recovery of aromatic carboxylic acid or ester thereof from the residue fraction of the oxidation or esterification reaction mixture resulting from the oxidation or oxidation and esterification of an aromatic compound having at least one methyl or formyl group directly bonded to a ring carbon atom. The process comprises treating the residue fraction with hydrogen and a hydrogenation catalyst.

Abstract: A novel vertical induced circulation reactor is utilized to carry out the oxidation of p-xylene and p-methyltoluate with air in the presence of a catalyst to produce p-toluic acid and monomethylterephthalate (MMT). A novel method for preparation of dimethylterephthalate (DMT) is provided wherein the p-toluic acid and MMT formed according to the invention are esterified by conventional means in the presence of methanol to produce p-methyl toluate and dimethylterephthalate (DMT), respectively, the p-methyl toluate being recycled to the reactor as a reactant stream.

Abstract: Unsaturated compounds having at least 4 carbon atoms, including unsaturated alicyclic compounds having at least 4 carbon atoms, unsaturated aliphatic compounds having at least one carbon-carbon unsaturated bond and having at least 4 carbon atoms and unsaturated aromatic compounds having at least one carbon-carbon unsaturated bond in the branched chain thereof and (ii) aldehydes or ketones having at least 4 carbon atoms are catalytically co-oxidized with an oxygen-containing gas in a liquid phase to form a cleaveged product or products of unsaturated bond of the unsaturated compounds at a high yield. This co-oxidation reaction is carried out in the presence of a heavy metal containing iron, cobalt, nickel, ruthenium, rhodium, palladium, osmium, iridium, platinum, copper, silver, chromium, molybdenum, tungsten, manganese and rhenium and the compounds thereof.

Abstract: Methyl-substituted polyphenylacyl compounds are prepared by selective oxidation of oligomers of mesitylene. These methyl-substituted polyphenylacyl compounds are useful as intermediates for polyamides and polyesters. The esters are useful as plasticizers for polyvinylchloride.

Abstract: A carboxylic ester is produced in one step in a high yield and with a high selectivity by reacting an aldehyde with an alcohol in the presence of oxygen by using a catalyst comprising (I) palladium, (II) at least one compound selected from the group consisting of lead compounds, thallium compounds and mercury compounds and (III) at least one compound selected from the group consisting of alkali metal compounds and alkaline earth metal compounds.

Abstract: Disclosed is a process for recovering dimethyl terephthalate and intermediate products from the tarry fraction of the residue generated in the production of dimethyl terephthalate from p-xylene and methanol by the cooxidation procedure. In the process the tarry fraction is established in admixture with a catalytic quantity of alkali metal material, examples of which are sodium and potassium carbonate, at about 200.degree.-350.degree. C., and the resulting reaction mixture is maintained in this temperature range until at least a substantial quantity of dimethyl terephthalate has formed. Generally, dimethyl terephthalate and intermediate products are separated from the reaction mixture. The separation in preferred embodiments is by distillation.

Abstract: A process for the preparation of aromatic ethers by the bromination of a compound of the formula ##STR1## wherein R.sub.1, independently, is hydrogen, hydroxy, lower alkoxy, lower alkyl; m is an integer from 1-4, and A is --CHO, --COOR.sub.3 or lower alkyl, and subsequently treating the reaction product of the bromination step with an alkali metal alkoxide in the presence of cuprous halide or oxide, is described.

Abstract: Aromatic esters are formed directly from aromatic aldehydes by reacting the aldehyde with molecular oxygen and an alcohol in the presence of a heterogeneous molybdenum oxidation catalyst.

Abstract: A process for producing dimethyl terephthalate from high-boiling tarry residues from the combined oxidation of p-xylene and p-toluate in the liquid phase, esterification of the resulting acids with methanol and separation of the resulting dimethyl terephthalate which include the steps of subjecting the high-boiling residues to treatment with methanol at temperatures above 250.degree. C. and thereafter separating the resulting dimethyl terephthalate in accordance with conventional separation techniques.

Abstract: Process for production of dipropyleneglycol dibenzoate isomer mixture of the formulas: ##STR1## A crude methyl benzoate containing at least 80 wt.% methylbenzoate, which is a by-product of production of dimethylterephthalate by catalytic oxidation of p-xylene and/or methyl-p-toluate and esterification of the resulting acids with methanol, is contacted with dipropylene glycol commercial isomer mixture in the presence of a catalyst for a transesterification to produce said benzoate. The catalyst is an aluminum alkoxide or an aluminum silicon alkoxide containing the group Al O Si. The product is obtained in good yield, has good color, and is useful as a plasticizer for PVC.

Abstract: In the process for preparing dimethyl terephthalate by oxydizing p-xylene and/or methyl p-toluate with molecular oxygen or a molecular oxygen-containing gas in the presence of a heavy metal catalyst, esterifying the resulting oxidation reaction mixture with methanol, followed by submitting the resulting esterification reaction mixture to distillation to separate dimethyl terephthalate and fractions of lower boiling point than dimethyl terephthalate, and thereafter recycling to said oxidation step (A) the distillation residue containing said heavy metal catalyst and/or (B) the extract portion containing said heavy metal catalyst obtained by further extraction treatment of said distillation residue (A), the improvement which comprises contact-treating said distillation residue (A) or said extract portion (B) with methanol prior to recycling same.

Abstract: A process for the production of dimethyl terephthalate and intermediate products of the dimethyl terephthalate manufacture from the high-boiling by-products obtained during the air oxidation of p-xylene and methyl p-toluate in the liquid phase, subsequent esterification of the thus-formed acids, and separation of the thus-produced esters, which comprises treating said high-boiling by-products with methanol at an elevated temperature and then separating the resultant product rich in dimethyl terephthalate by distillation with the addition of a carrier gas or a carrier vapor.