Abstract: It is an object of the present invention to provide a method for producing (meth)acrylic anhydride that provides high yield and high efficiency and can suppress side reactions, in a method for reacting (meth)acrylic acid with a fatty acid anhydride to produce (meth)acrylic anhydride. The method for producing (meth)acrylic anhydride according to the present invention is a method for producing (meth)acrylic anhydride, including reacting a fatty acid anhydride with (meth)acrylic acid to produce (meth)acrylic anhydride, while extracting a fatty acid produced as a by-product, wherein the reaction is performed, while adjustment is performed so that a molar ratio of the (meth)acrylic acid to the (meth)acrylic anhydride in a reaction liquid is 0.3 or more.

Abstract: It is an object of the present invention to provide a method for producing (meth)acrylic anhydride that provides high yield and high efficiency and can suppress side reactions, in a method for reacting (meth)acrylic acid with a fatty acid anhydride to produce (meth)acrylic anhydride. The method for producing (meth)acrylic anhydride according to the present invention is a method for producing (meth)acrylic anhydride, including reacting a fatty acid anhydride with (meth)acrylic acid to produce (meth)acrylic anhydride, while extracting a fatty acid produced as a by-product, wherein the reaction is performed, while adjustment is performed so that a molar ratio of the (meth)acrylic acid to the (meth)acrylic anhydride in a reaction liquid is 0.3 or more.

Abstract: A process for preparation of 7-[D-?-amino-?-(4-hydroxyphenyl)acetamido]-3-(1-propen-1-yl)-3-cephem-4-carboxylic acid viz. Cefprozil of formula (I) in high purity, substantially free of impurities, which comprises preparation of mixed acid anhydride by selecting the sequence and temperature of addition of the reagents and its subsequent condensation with a protected 7-APCA; followed by hydrolysis, isolation and purification to give Cefprozil of formula (I) in the form of a monohydrate.

Abstract: The novel process for preparing dialkyl dicarbonates by reacting the corresponding alkyl haloformates with alkali metal hydroxides, alkaline earth metal hydroxides and/or carbonates in the presence of water-immiscible organic solvents and in the presence of a catalyst is characterized in that the catalyst used is at least one tertiary alkylamine of the formula (I) NR1R2R3,??(I) where the substituents are each as defined in the description.

Abstract: The present invention relates to a process for preparing an unsaturated carboxylic acid anhydride by reacting an unsaturated carboxylic acid and a lower aliphatic carboxylic acid anhydride in the presence of a stabilizer and catalyst that contains a metal salt of an anionic organic compound which has at least one carboxyl group.

Abstract: A method of producing (RfCo)2O by reacting RfCOCl with MmCO3 can efficiently synthesize a fluorocarboxylic anhydride in a one-step reaction,

Abstract: Disclosed is a process for the preparation of trifluoromethanesulfonic acid anhydride by the steps of (1) forming a mixed anhydride comprising a trifluoromethanesulfonyl acyl residue and a carboxyl residue by contacting trifluoromethanesulfonic acid or a derivative thereof with a carboxyl compound selected from ketene, dialkyl ketenes, carboxylic acids, and derivatives of carboxylic acids and (2) subjecting the mixed anhydride to reactive distillation wherein the mixed anhydride undergoes disproportionation to produce triflic anhydride and a higher boiling carboxylic acid anhydride.

Abstract: The invention concerns a method consisting in making a mixed (meth)acrylic anhydride of formula (I) by reacting an alkaline (meth)acrylate of formula (II) and a chloroformate of formula (III), carrying out said reaction in an aqueous medium and in the absence of amines, the mol ratio chloroformate (III)/alkaline (meth)acrylate (II) being at least equal to 1.15. R1 represents H or CH3; R2 represents an alkyl, alkenyl, aryl, alkaryl or aralkyl residue; and M is an alkaline metal.

Abstract: The retrofitting of an existing methanol or methanol/ammonia plant to make acetic acid is disclosed. The plant is retrofitted to feed carbon dioxide into a reformer to which natural gas and steam (water) are fed. Syngas is formed in the reformer wherein both the natural gas and the carbon dioxide are reformed to produce syngas with a large proportion of carbon monoxide relative to reforming without added carbon dioxide. The syngas is split into a first part and a second part. The first syngas part is converted to methanol in a conventional methanol synthesis loop that is operated at about half of the design capacity of the original plant. The second syngas part is processed to separate out carbon dioxide and carbon monoxide, and the separated carbon dioxide is fed back into the feed to the reformer to enhance carbon monoxide formation. The separated carbon monoxide is then reacted with the methanol to produce acetic acid or an acetic acid precursor by a conventional process.

Abstract: Polymer-bound mixed carboxylic anhydrides can be prepared under mild conditions by the condensation of carboxylic acids (including N-protected amino acids) with polymer-bound acid chlorides. These mixed anhydrides function as polymeric reagents in the sense that they will react readily with monomeric nucleophiles such as amines to form amide or peptide products, depending on the identities of the mixed anhydride and amine reactants. However, in spite of their reactivity, these polymeric mixed anhydrides exhibit a significant degree of stability under conditions of prolonged storage, which suggests that such compounds have commercial utility as a relatively stable form of highly activated carboxylic acids. The polymeric support can be reactivated and recycled for repeated use in the derivatization process.

Abstract: Dialkyl dicarbonates are obtained particularly advantageously from halogenoformic esters by reaction with alkalis in the presence of water-immiscible organic solvents and in the presence of a catalyst, if the catalyst used is benzylalkyldimethylammonium halides. The catalyst is then particularly easy to separate off and to recycle from the reaction mixture.

Abstract: Polymer-bound mixed carboxylic anhydrides can be prepared under mild conditions by the condensation of carboxylic acids (including N-protected amino acids) with polymer-bound acid chlorides. These mixed anhydrides function as polymeric reagents in the sense that they will react readily with monomeric nucleophiles such as amines to form amide or peptide products, depending on the identities of the mixed anhydride and amine reactants. However, in spite of their reactivity, these polymeric mixed anhydrides exhibit a significant degree of stability under conditions of prolonged storage, which suggests that such compounds have commercial utility as a relatively stable form of highly activated carboxylic acids. The polymeric support can be reactivated and recycled for repeated use in the derivatization process.

Abstract: Solid-phase copolymers of 4-vinylpyridine or 4-vinylpyridine 1-oxide may be employed as catalysts in the formation of acid anhydrides. A water soluble polymer of 4-vinylpyridine 1-oxide may also be employed as a catalyst in the formation of acid anhydrides.