Maleic acid: anhydride from hydrogenation

In a very recent publication, Bergbreiter, and co-workers studied the extension of this concept using the pH value as a regulatory variable [20 b]. A phosphine-modified polyacid (a copolymer from methyl vinyl ether and maleic acid anhydride, Gantrez ) was taken as a ligand for rhodium. The rate of hydrogenation of various unsaturated substrates was reversibly modified by tuning the pH value. 

A new process to manufacture THF and 1,4 butanediol from maleic anhydride is currently slated for start-up by DuPont in Asturias, Spain in 1996. The process involves the oxidation of n-butane in a transport bed reactor to form maleic anhydride. Recovery of maleic anhydride is accomplished by scrubbing with water which converts the anhydride immediately to maleic acid. The maleic acid is then hydrogenated to tetrahydrofuran in a bubble column reactor. By varying operating conditions in the hydrogenation reactor the alternate or coproduction of 1,4 butanediol can be accomplished. 

DuPont recently commercialized a new process for the oxidation of butane to maleic anhydride using a CSR. The maleic anhydride is scrubbed from the reaction zone as maleic acid and then hydrogenated to tetrahydrofuran. The advantages are well documented in the references. A key to this process was the development of an attrition-resistant catalyst obtained by spray-drying a solution of micronized vanadium-phosphorus-oxygen (VPO) catalysts in polysilicic acid. In the spray dryer, a porous shell of very hard silica is formed to protect the soft VPO catalyst. 

A. Maleic acid. Assemble the apparatus shown in Fig. Ill, 28, 1. Place 45 g. of dry mahc acid in the 200-250 ml. distilling flask and cautiously add 63 g. (57 ml.) of pure acetyl chloride. Warm the flask gently on a water bath to start the reaction, which then proceeds exothermically. Hydrogen chloride is evolved and the malic acid passes into solution. When the evolution of gas subsides, heat the flask on a water bath for 1-2 hours. Rearrange the apparatus and distil. A fraction of low boiling point passes over first and the temperature rises rapidly to 190° at this point run out the water from the condenser. Continue the distillation and collect the maleic anhydride at 195-200°. Recrystallise the crude maleic anhydride from chloroform (compare Section 111,93) 22 g. of pure maleic anhydride, m.p. 54°, are obtained. 

Survey of the patent Hterature reveals companies with processes for 1,4-butanediol from maleic anhydride include BASF (94), British Petroleum (95,96), Davy McKee (93,97), Hoechst (98), Huels (99), and Tonen (100,101). Processes for the production of y-butyrolactone have been described for operation in both the gas (102—104) and Hquid (105—108) phases. In the gas phase, direct hydrogenation of maleic anhydride in hydrogen at 245°C and 1.03 MPa gives an 88% yield of y-butyrolactone (104). Du Pont has developed a process for the production of tetrahydrofuran back-integrated to a butane feedstock (109). Slurry reactor catalysts containing palladium and rhenium are used to hydrogenate aqueous maleic acid to tetrahydrofuran (110,111). 

The catalyst used in the production of maleic anhydride from butane is vanadium—phosphoms—oxide (VPO). Several routes may be used to prepare the catalyst (123), but the route favored by industry involves the reaction of vanadium(V) oxide [1314-62-1] and phosphoric acid [7664-38-2] to form vanadyl hydrogen phosphate, VOHPO O.5H2O. This material is then heated to eliminate water from the stmcture and irreversibly form vanadyl pyrophosphate, (V(123,124). Vanadyl pyrophosphate is befleved to be the catalyticaHy active phase required for the conversion of butane to maleic anhydride (125,126). 

Manufacturing. Almost all the THE in the United States is currendy produced by the acid-catalyzed dehydration of 1,4-butanediol [10-63-4]. Only one plant in the United States still makes THE by the hydrogenation of furfural (29). Du Pont recendy claimed a new low cost process for producing THE from / -butane that they plan to commercialize in 1995 (30—32). The new process transport-bed oxidizes / -butane to cmde maleic anhydride, then follows with a hydrogen reduction of aqueous maleic acid to THE (30). 

Diels et al. showed that acetylenedicarboxylic acid and 1-methyl-pyrrole gave l-methyl-2-pyrrylmaleic anhydride (41) and a second compound. The anhydride on hydrogenation and conversion to the corresponding dimethyl ester gave the same product as obtained from 1-methylpyrrole and maleic anhydride, followed by hydrolysis and... 

The production of 1,4-butanediol (1,4-BDO) from propylene via the carbonylation of allyl acetate is noted in Chapter 8. 1,4-Butanediol from maleic anhydride is discussed later in this chapter. An alternative route for the diol is through the acetoxylation of butadiene with acetic acid followed by hydrogenation and hydrolysis. 

The simplest unsaturated dicarboxylic acids are maleic acid and fumaric acid, both of which are cheap, commercially available, materials. They are geometric isomers maleic acid is the (Z) isomer (19), and fumaric acid is the (E) isomer (20). Maleic acid forms an internal anhydride, maleic anhydride (21), which is widely used to form adducts with conjugated dienes (the Diels-Alder reaction, Section 7.6). The formation of the anhydride from maleic acid and the conversion of maleic acid into fumaric acid are described in Expt 5.218. The hydrogenation of maleic acid to succinic acid is of value as a means of evaluating the activity of a catalyst for use in hydrogenations at atmospheric pressure the experimental procedure is given in Section 2.17.1, p. 87. 

Butane can be used for the manufacture of maleic acid (thence to maleic anhydride), from which tetrahydrofuran is made by hydrogenation. Liquefied petroleum gas is also a feedstock for aromatics production (Fig. 1). 

Sodium amalgam serves to reduce selectively the double bond in an olefinic acid containing the thiophene or furan ring. " This reagent is also employed to prepare olefinic acids by partial reduction of certain polyenoic acids, e.g., 3-pentenoic acid (60%) from vinylacrylic acid. Among the dibasic acids prepared by this method are succinic acid from maleic acid (98%) by catalytic hydrogenation over Raney nickel catalyst and alkylsuccinic acids from alkenylsuccinic acids made by the Diels-Alder reaction of simple olefins and maleic anhydride. ... 

The hydrogenation of substituted succinic anhydrides such as 65, over platinum oxide at room temperature and 3-4 atmospheres leads to the initial formation of the hydroxy lactone, 66. Further hydrogenation in acetic acid at the same temperature and pressure converts 65 into a 2 1 ratio of the lactone, 67 and the methyl acid, 68. Extended hydrogenation of the anhydride in ethyl acetate gave almost equal amounts of 67 and 68 (Eqn. 18.42). Since anhydrides such as 65 are available from Diels-Alder reactions with maleic anhydride, this procedure has synthetic utility since the hydrogenations take place exclusively on the least hindered carbonyl group of the anhydride. 

Derivation Occurs naturally in wine lees made synthetically from maleic anhydride and hydrogen peroxide and by an enzymatic reaction with a succinic acid derivative. 

A further requirement for the high selectivity to maleic anhydride from n-butane is the need for a correct sequence of oxidehydrogenation and oxygen insertion reactions. In the oxidation of n-butane the olefinic-like intermediate must be quickly oxidehydrogenated to an adsorbed dienic-like compound in order to favour the selective pathway towards maleic anhydride. In fact, this reaction may occur concurrently with the oxidation of allylic carbon atoms, with formation of aldehydes and acids which can also be precursors of carbon oxides. Thus, the selectivity to maleic anhydride depends on the relative rates of hydrogen abstraction and oxygen insertion. This property can be considered as typical of the vanadyl pyrophosphate for instance, in the case of the V/Mo/0 system the rate of oxygen insertion... 

By retro synthetic analysis collagenase inhibitor RO0319790 (1) can be assembled from two chiral building blocks, (R) -succinate 2 and (S)-tert-leucine N-methyla-mide 13. As the latter can be prepared from commercially available (S)-tert-leucine 8 our work concentrated in particular on the construction of the first building block 2. In order to assemble the carbon skeleton of 2 in the most efficient way, extremely cheap maleic anhydride 4 was converted in a known ene reaction with isobutylene to provide the cyclic anhydride 6. Hydrogenation of the double bond followed by the addition of EtOH/p-TsOH yielded the racemic diethyl ester substrate 9 for the enzyme reaction. The enzymatic monohydrolysis of 9 afforded the monoacid (R)-2a. (R)-2 a was coupled via its acid chloride with leucine amide 13 to ester 14, which finally was converted into the hydroxamic acid 1. 

There are several industrial processes for succinic acid production (1) oxidation of paraffins forms a mixture of different carboxylic acids, followed by separation of succinic acid (2) catalytic hydrogenation of maleic acid or trani-maleic acid (3) electrochemical synthesis from maleic anhydride in a bipolar membrane or nonmembrane cell (4) production from acetylene, carbon monoxide, and water catalyzed by [Cq(CO) ] in an acid medium under a pressure of 2.94-49.03 MPa at 80-250°C. Among them, electrochemical synthesis is a generally applied process for succinic acid, which has the advantage of high yield, low cost, high purity of... 

The reaction of excess amounts of methyl acrylate and the self-metathesis products of monounsaturated fatty acids like methyl ester of oleic acid with ethylene, produces valuable monomers for polycondensation polymers, as well as precursors for detergents in the presence of a suitable metathesis catalyst. In oleochemistry, azaleic and pelargonic acid were obtained industrially by ozonolysis of oleic acid. Non-linear fatty acid derivatives with two double bonds, (ricinoleic acid maleate) and one double bond (ricinoleic acid succinate) were produced from ricinoleic acid by esterification with maleic and succinic anhydride, respectively. Hydrogenation of this ricinoleic acid succinate yielded 12-hydroxystearic acid succinate which is a monomer for vegetable oil-based polyester. 

The other important aspect of the development of the succinic acid market is the chemical conversion of succinic acid to other products. Selective and low-cost catalyst development is needed to enable lower-cost economics. The chemistry of succinic acid catalysis has been reviewed by Varadarajan and Miller (1999), and the summary of the various derived products that follow is from that work. Succinic acid can be readily converted into alkyl esters that have uses as industrial solvents and paint removers. Succinic acid, its anhydride or its esters, can be hydrogenated to the product family of 1,4-butanediol however, this conversion has not been as well studied as the hydrogenation of maleic acid or anhydride. A third important product family that can be derived from ammonium succinate, succinimide, or succinic acid is based on 2-pyrroHdinones. They are used for polyvinylpyrrolidone (PVP) production, which has an estimated minimum market value of 150 million per year. Other uses for 2-pyrrolidinones include solvents and plasticizers. The commercial production depends upon petrochemical-based... 

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