Of maleic acid

Krilium The trade name of a soil conditioner. The solid form of Krilium has as active in-gredienl a copolymer of about equal molar proportions of vinyl ethanoate and the partial methyl ester of maleic acid. It may be formulated with lime, bentonite, etc. In aqueous form, Krilium contains a copolymer of about equal molar proportions of isobutene and ammonium maleamate. Other polymers are also used. 

H02C(CH2)2C02H. Colourless prisms m.p. 182 C, b.p. 235°C. Occurs in amber, algae, lichens, sugar cane, beets and other plants, and is formed during the fermentation of sugar, tartrates, malates and other substances by a variety of yeasts, moulds and bacteria. Manufactured by the catalytic reduction of maleic acid or by heating 1,2-dicyanoethane with acids or alkalis. Forms an anhydride when heated at 235°C. Forms both acid and neutral salts and esters. Used in the manufacture of succinic anhydride and of polyesters with polyols. 

Mesotartaric acid crystallizes in plates (IHjO), m.p. 140 C (anhydrous). Very soluble in water. Obtained from the mother-liquors in the preparation of racemic acid or by oxidation of maleic acid. Potassium hydrogen mesotartrale is soluble in water. 

Mix 100 g. of maleic acid (Section 111,143) and 100 ml. of tetra chloroethane in a 250 ml. Claisen or distilling flask provided with a thermometer, and attach a Pyrex Liebig condenser. Heat the flask in an air bath (Fig. 11, 5, 3) and collect the distillate in a measuring cylinder. When the temperature reaches 160°, 76 ml. of tetrachloroethane and 15-15-5 ml. of water are present in the receiver. Empty the water in the condenser and continue the distillation change the receiver when the temperature reaches 190°. Collect the maleic anhydride at 195-197°. Recrystallise the crude anhydride from chloroform. The yield of pure maleic anhydride, m.p. 54°, is 70 g. 

B. Conversion of maleic acid into fumaric acid. Dissolve 10 g. of maleic acid in 10 ml. of warm water, add 20 ml. of concentrated hydrochloric acid and reflux gently (provide the flask with a reflux condenser) for 30 minutes. Crystals of fumaric acid soon crystaUise out from the hot solution. Allow to cool, filter oflF the fumaric acid, and recrystallise it from hot. A -hydrochloric acid. The m.p. in a sealed capillary tube is 286-287°. 

Washing and cleaning agents containing salts of maleic acid—furan copolymers (106) form complexes with alkaline-earth ions. These cleaning compositions do not contain phosphoms or nitrogen and find use in metal, foodstuff, and machine dishwashing products. 

Fum ric Acid. Eumaric acid [110-17-8] C H O, is unique in its low solubiUty in cold water and slow rate of solution, making it ideal for use in chilled biscuit leavening systems and for dry pudding mixes and beverage powders. It is also used for gelatin desserts, pie filling, fmit juices, and wine. Eumaric acid is produced by the acid-catalyzed isomerization of maleic acid (8,9) (see Maleic anhydride, maleic acid, and fumaric acid). 

Commercial Synthesis ofR,S-Mahc Acid. The commercial synthesis of R%-mahc acid involves hydration of maleic acid [110-16-7] or fumaric acid [110-17-8] at elevated temperature and pressure. A Japanese patent (33) describing a manufacturing procedure for malic acid claims the direct hydration of maleic acid at 180°C and 1.03—1.21 MPa (150—175 psi). 

The initial step of production is carried out in a titanium reactor (34) because of the high corrosivity of maleic acid to most metals under the drastic reaction conditions used. The other steps are performed in stainless steel equipment. Improved purification processes for malic acid have been patented (37,38). 

R, R -Tartaric (racemic) acid is obtained synthetically by epoxidation of maleic acid with hydrogen peroxide in the presence of a catalyst followed... 

Maleic anhydride and the two diacid isomers were first prepared in the 1830s (1) but commercial manufacture did not begin until a century later. In 1933 the National Aniline and Chemical Co., Inc., installed a process for maleic anhydride based on benzene oxidation using a vanadium oxide catalyst (2). Maleic acid was available commercially ia 1928 and fumaric acid production began in 1932 by acid-catalyzed isomerization of maleic acid. 

Isomerization. Maleic acid is isomerized to fumaric acid by thermal treatment and a variety of catalytic species. Isomerization occurs above the 130 to 140°C melting point range for maleic acid but below 230°C, at which point fumaric acid is dehydrated to maleic anhydride. Derivatives of maleic acid can also be isomerized. Kinetic data are available for both the uncatalyzed (73) and thiourea catalyzed (74) isomerizations of the cis to trans diacids. These data suggest that neither carbonium ion nor succinate intermediates are involved in the isomerization. Rather, conjugate addition imparts sufficient single bond character to afford rotation about the central C—C bond of the diacid (75). 

Process Technology Evolution. Maleic anhydride was first commercially produced in the early 1930s by the vapor-phase oxidation of benzene [71-43-2]. The use of benzene as a feedstock for the production of maleic anhydride was dominant in the world market well into the 1980s. Several processes have been used for the production of maleic anhydride from benzene with the most common one from Scientific Design. Small amounts of maleic acid are produced as a by-product in production of phthaHc anhydride [85-44-9]. This can be converted to either maleic anhydride or fumaric acid. Benzene, although easily oxidized to maleic anhydride with high selectivity, is an inherently inefficient feedstock since two excess carbon atoms are present in the raw material. Various compounds have been evaluated as raw material substitutes for benzene in production of maleic anhydride. Fixed- and fluid-bed processes for production of maleic anhydride from the butenes present in mixed streams have been practiced commercially. None of these... 

The test methods used by industry to determine if a sample of maleic anhydride is within specifications (165) ate ASTM methods D2930, D1493, and D3366. These methods describe procedures for the determination of maleic acid content, the crystallization point, and the color properties of the maleic anhydride sample, respectively. By quantitative deterrnination of these properties, a calculation of the overall purity of the maleic anhydride sample can be made. 

Other minor raw materials are used for specific needs. Eumaric acid [110-17-8] the geometric isomer of maleic acid, is selected to maximize thermal or corrosion performance and is the sole acid esterified with bisphenol A diol derivatives to obtain optimum polymer performance. CycloaUphatics such as hydrogenated bisphenol A (HBPA) and cyclohexanedimethanol (CHDM) are used in selective formulations for electrical apphcations. TetrahydrophthaUc anhydride [85-43-8] (THPA) can be used to improve resiUence and impart useful air-drying properties to polyester resins intended for coating or lining apphcations. 

Succinic anhydride [108-30-5] (3,4-dihydro-2,5-furandione butanedioic anhydride tetrahydro-2,5-dioxofuran 2,5-diketotetrahydrofuran succinyl oxide), C H O, was first obtained by dehydration of succinic acid. In the 1990s anhydride is produced by hydrogenation of maleic anhydride and the acid by hydration of the anhydride, by hydrogenation of aqueous solutions of maleic acid, or as a by-product in the manufacture of adipic acid (qv) (see Maleic ANHYDRIDE, MALEIC ACID, AND FUMARIC ACID). 

Other preparations of succinic acid mentioned in the Hterature are electrochemical reduction of maleic or fumaric acid (153,154), ultrasound-promoted Zn—acetic acid reduction of maleic or fumaric acid (155), reduction of maleic acid with H2PO2 at room temperature (156),... 

An alternative approach is first to produce a polyester resin containing an excess of maleic acid residues (maleate groups) and then to react this with the hexachlorocyclopentadiene to form the adduct in situ Figure 25.S). 

Preparation of 4-aza-S-(N-methyi-4-piperidyiidene)-10,11-dihydro-SH-dibenzo[a,d]cyciohep-tene dimaieate To a solution containing 4.3 g of 4-aza-(N-methyl-4-piperldylidene)-10,11-dihydro-5H-dibenzo[a,d] cycioheptene in 55 ml of ethyl acetate, add a solution of 3.45 g of maleic acid dissolved in ethyl acetate. Filter the resulting precipitate and recrystallize the desired product from an ethyl acetate-methanol mixture to yield 4-aza-5-(N-methyl-4-pi-perldylidene)-10,11 -dihydro-5H-dibenzo[a/d] cycloheptene dimaieate, MP 152°-154°C. 

The mixture is refluxed with stirring for ten hours, cooled and filtered. The filtrate is extracted three timas with 200 cc portions of 6 N acetic acid. The aqueous acetic acid solution is then made strongly basic with 10% sodium hydroxide solution, and extracted three times with 200 cc portions of ether. The ether extract is dried with anhydrous sodium sulfate, stirred with 5 g of activated carbon and filtered to provide 2-[p-chloro-a(2-di-methylaminoethoxylbenzyll pyridine in solution. Addition of a solution of 116 g (1 mol) of maleic acid in 1,500 cc of ether gives 323 g (79%) of solid which, on recrystallization from ethyl acetate, gives white solid 2-[p-chloro-a(2-dimethvlaminoethoxv)benzyl] pyridine maleate melting at 117° to 119°C. 

A mixture of 5.0 g of 3-chloro-5-(3-chloropropyl)-10,11 -dihydro-5H-dibenz(b,f)azepine, 5.0 g of 4-carbamoyl-4-piperidinopiperidine and 50 mi of dimethylformamide is heated at 100°C for 10 hours. The solvent is distilled off. After the addition of a 2% sodium carbonate solution to the flask, the content is scratched to yield a semisolid, which is dissolved in 50 ml of isopropanol. A solution of 5 g of maleic acid in 50 ml of isopropanol is added, and the precipitate is collected by filtration and recrystallized from isopropanol to give 5.6 g of crystalline 3-chloro-5-[3-(4-carbamoyl-4-piperidino-piperidino)propy I] -10,1 l-dihydro-SH-dibenz-Ib.fjazepine dilhydrogen maleate) with 1/2 molecule of water of crystallization melting at 181°C to 183°C. 

To a solution of 1.0 gram of 2-(2-dimethylaminoethyl)-3-[ 1-(2-pyridyl)-ethyl]-indene in 10 ml of ethanol is added while stirring and heating 0.4 gram of maleic acid. On cooling the 2-(2-dimethylaminoethyl)-3-[ 1-(2-pyridyl)-ethyl]-indene maleate crystallizes, is filtered off, washed with a small amount of ethanol and recrystallized from ethanol, MP 158°C. 

A warm solution of 6.5 g (0.02 mol) of 6-chloro-6-(2-fluorophenyl)-1-methyl-4H-imidazo-[13-a] [1,4] -benzodiazepine in 30 ml of ethenol wes combined with a warm solution of 2.6 g (0.022 mol) of maleic acid in 20 ml of ethenol. The mixture was diluted with 150 ml of ether and heated on the steam bath for 3 minutes. After cooling, the crystals were collected, washed with ether and dried in vacuo to yield 8-chloro-6-(2-fluorophenyl)-1-methyl-4H-imidazoM, 5-a] [1,4] -benzodiazepine maleete, melting point 148°C to 151°C. 

The hydrochloride salt was neutralized with 10% sodium hydroxide solution and the free base so produced was dissolved in ether. The ether solution was dried over anhydrous magnesium sulfate. Addition of an excess of maleic acid in methanol to the solution yielded the acid maleate salt which melted at 188.5°-191°C. 

Chloro-lO-13-(di-N-2-chloroethvl)aminopropvl)lphenthiazine hydrochloride (1.8 g) is heated in a sealed tube for 4 hours at 140°C with a 290 g/l aqueous solution (9 cc) of monomethylpiperazine. The contents of the tube are treated with chloroform (40 cc). The aqueous layer is decanted and the chloroform layer is shaken with N hydrochloric acid (15 cc followed by 2 cc). The aqueous solution is treated with sodium hydroxide (d = 1.33, 10 cc) and chloroform (20 cc). After evaporation of the solvent, the base (1.5 g) is obtained. A solution of maleic acid (1 g) in ethanol (5 cc) is added and after recrystallization from water, 3-chloro-10-13-(4 -methyl-1 -piperazinvDpropyll phenothiazine dimaleate is obtained, melting point 228°C (inst.). 

Alternative Step D Reduction with a Reductate — Sucrose (1 kg) is dissolved in water (9 liters) in a 20-liter bottle equipped with a gas trap. Baker s yeast Saccharomyces cerevisiae, 1 kg) is made into a paste with water (1 liter) and added to the sucrose solution with stirring. After lively evolution of gas begins (within 1 to 3 hours), 3-morpholino-4-(3-tert-butylamino-2-oxopropoxy)-1,2,5-thiadiazole hydrogen maleate [1.35 mols, prepared by reaction of the 3-morpholino-4-(3-tert-butylamino-2-oxopropoxy)-1,2,5-thiadiazole with an equimolar quantity of maleic acid in tetrahydrofuran]. The mixture is allowed to stand until fermentation subsides, after which the bottle is kept in a 32°C incubator until all fermentation has ended (in approximately 1 to 3 days). The yeast is filtered off with addition of diatomaceous earth and the filtrate is evaporated to dryness to give S-3-mor-pholino-4/3-tert-butylamino-2-hydroxypropoxy)-1,2,5-thiadiazole, MP 195° to 198°C (as hydrogen maleate), according to U.S. Patent 3,619,370. 

Using benzene as starting material the yield of maleic acid anhydride is about 70 mol %. Using n-C4 hydrocarbons only about 50 mol % yield is obtained. But due to the lower molecular weights of the C4 olefins the wt % values are about 90% in both cases. 

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