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Synthesis dicarboxylic acids from

Actual operating capacities of Reppe carbonylation processes are difficult to estimate since only a few data are available in the literature. However, it is known that some of the syntheses are carried out on an industrial scale, e. g. the synthesis of acrylates from acetylene, carbon monoxide and alcohols (BASF) [1004, 1005], the acetic acid synthesis from methanol and carbon monoxide and the synthesis of higher molecular weight saturated carboxylic acids from olefins, carbon monoxide and water. Propionic acid (30,000 tons/year) and to a smaller extent heptadecanoic dicarboxylic acid are manufactured via the carbonylation route at BASF. Butanol is made from propylene in Japan [1003, 1004]. [Pg.120]

Synthesis of Thiophene-2,5-Dicarboxylic Acid Derivatives from Thiodiacetates... [Pg.7]

Methylenedioxythiophene-2,5-dicarboxylic acid synthesis. (Data from F. Dallacker and V. Mues, 1975, Chem Ber 108 569-575.)... [Pg.294]

Regioselectivity of C—C double bond formation can also be achieved in the reductiv or oxidative elimination of two functional groups from adjacent carbon atoms. Well estab llshed methods in synthesis include the reductive cleavage of cyclic thionocarbonates derivec from glycols (E.J. Corey, 1968 C W. Hartmann, 1972), the reduction of epoxides with Zn/Nal or of dihalides with metals, organometallic compounds, or Nal/acetone (seep.lS6f), and the oxidative decarboxylation of 1,2-dicarboxylic acids (C.A. Grob, 1958 S. Masamune, 1966 R.A. Sheldon, 1972) or their r-butyl peresters (E.N. Cain, 1969). [Pg.142]

A second method makes use of the lactone (31) from acetone dicarboxylate (40) and for which a synthesis from (—)-carvone has been reported (41). Displacement of chlorine from the 6-aminopenici11anic acid (6-APA) derived P-lactam (32) by (33) illustrates yet another approach to the dia2oketone (28) (42). [Pg.7]

Pyrrole-2,3-dialdehyde, 1-methyl-pyrrolopyridazine synthesis from, 4, 517 Pyrrole-2,5-dicarboxylic acid, 3,4-dihydroxy-l-phenyl-diethyl ester... [Pg.818]

There are two series of benzisothiazoles, derived from benz[c]iso-thiazole (2) and benz[d]isothiazole (3), and both, if the benzene ring were suitable weakened, could doubtless be oxidized to isothiazole-dicarboxylic acids. In their first synthesis Adams and Slack... [Pg.108]

Reaction of -picoline over degassed Raney nickel was found to give 5,5 -dimethyl-2,2 -bipyridine (5), the structure of which was established by its synthesis from 2-bromo-5-methylpyridine. Oxidation of this dimethyl-2,2 -bipyridine, and similar oxidation of the diethyl-2,2 -bipyridine derived from 3-ethylpyridinc, gave the corresponding dicarboxylic acid and the same acid was produced by the action of degassed Raney nickel on sodium nicotinate (in water) or on ethyl nicotinate. These transformations established the 5,5 -substitution pattern for three 2,2 -bipyridines derived from 3-substituted pyridines but such evidence is not available for the biaryls... [Pg.184]

Cefpimizole (51) appears to be less active in vitro than cefotaxime and cefoperazone and to have a somewhat narrower activity spectrum although some strains of Pseudomonas are susceptible. It is not orally active, but its performance in vivo appears superior to what would be expected from its in vitro data. Its synthesis begins by acylation of cephaloglycin (48) with the bis acid chloride of imidazole-4,5-dicarboxylic acid (49) to give amide 50. The acetyl moiety at C-3 of this intermediate is displaced with 4-pyridineethanesulfonic acid and sodium iodide to give cef-pimazole (51) [16]. [Pg.185]

Faraday, in 1834, was the first to encounter Kolbe-electrolysis, when he studied the electrolysis of an aqueous acetate solution [1], However, it was Kolbe, in 1849, who recognized the reaction and applied it to the synthesis of a number of hydrocarbons [2]. Thereby the name of the reaction originated. Later on Wurtz demonstrated that unsymmetrical coupling products could be prepared by coelectrolysis of two different alkanoates [3]. Difficulties in the coupling of dicarboxylic acids were overcome by Crum-Brown and Walker, when they electrolysed the half esters of the diacids instead [4]. This way a simple route to useful long chain l,n-dicarboxylic acids was developed. In some cases the Kolbe dimerization failed and alkenes, alcohols or esters became the main products. The formation of alcohols by anodic oxidation of carboxylates in water was called the Hofer-Moest reaction [5]. Further applications and limitations were afterwards foimd by Fichter [6]. Weedon extensively applied the Kolbe reaction to the synthesis of rare fatty acids and similar natural products [7]. Later on key features of the mechanism were worked out by Eberson [8] and Utley [9] from the point of view of organic chemists and by Conway [10] from the point of view of a physical chemist. In Germany [11], Russia [12], and Japan [13] Kolbe electrolysis of adipic halfesters has been scaled up to a technical process. [Pg.92]

An excellent synthesis of myristic acid is thus achieved from readily accessible starting materials. An alternative synthesis of myristic acid utilises hexanolc acid (M-caproic acid n-hexolc acid) (X) (2 mols) and methyl hydrogen sebacate (XI) (1 mol) the products, after hydrolysis, are n-decane (XII), myristic acid (XIII) and hexadecane-1 16-dicarboxylic acid (XIV) ... [Pg.938]

Fig. 8a, b. a Biosynthetic pathways for the major aliphatic components of suberin. b Representation of the active site of co-hydroxy acid dehydrogenase involved in the synthesis of the dicarboxylic acids characteristic of suberin. From [74]... [Pg.26]

Synthesis of polyanhydrides from the aromatic dicarboxylic acids (isophthalic and terephthalic acids) by melt polycondensation was first... [Pg.172]

FIGURE 6.30 Approaches for the synthesis of monosubstituted trifunctional amino acids. (A) Monoesterification of dicarboxylic acids. (B) Aa-Alkoxycarbonylation of lysine through the e-benzylidene derivative [Bezas Zervas, 1963]. (C) SelectiveN -detritylation of ditrityl derivatives.138 (D) A- AI ko x y met hy 1 at 10 n of histidine by displacement of AP-substituents.137 Cbz-His(CH2OR)-OMe are obtained from Cbz-His(xAc)-OMe. = Acylating reagent. [Pg.195]

The reaction of type i is utilized for the preparation of a variety of dicarboxylic acids. Scheme 25 shows the synthesis of a C-disaccharide (73) from a carbohydrate carboxylic acid (72) [98]. [Pg.186]

The above-mentioned concept of the synthesis of carboxylic acid functional hyperbranched polyesteramides is not limited to cyclic anhydrides as building blocks. It can be carried out with diisopropanolamine and any dicarboxylic acid as well. The same ratios as written above and calculated in Scheme 1 have been applied in the synthesis of carboxylic acid functional hyperbranched polyesteramides starting from adipic acid and diisopropanolamine. The first one (ratio 2.3 1) gelates as expected, the second one (ratio adipic acid diisopropanolamine 3.2 1) affords the expected product. Again, with GPC the amount of free adipic acid detected is in good agreement with theory (Fig. 17). [Pg.57]

The diacylation of isopropenyl acetate with anhydrides of dicarboxylic acids is applicable for the synthesis of several other cyclic jS-triketones in moderate yield. - It has been used for the synthesis of 2-acetylcyclohexane-l,3-dione (40% yield), 2-acetyl-4-methylcyclopentane-l,3-dione (10% yield), 2-acetyl-4,4-dimethylcyclopentane-l,3-dione (10% yield), 2-acetyl-5,5-dimethylcyclohexane-l,3-dione (10% yield), 2-acetylcyclo-heptane-l,3-dione (12% yield) and 2-acetylindane-l,3-dione (26% yield). Maleic anhydrides under more drastic conditions give acetylcyclopent-4-ene-l,3-diones in yields from 5% to 12%. The corresponding acylation of the enol acetate of 2-butanone with succinic anhydride has been used to prepare 2-methylcyclopentane-l,3-dione, an important intermediate in steroid synthesis. - ... [Pg.3]


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