Crotonate, potassium

Sodium crotonate on heating in solid state gave hex-l-ene-3,4-dicarboxylate (A). On the other hand, potassium crotonate on heating at 320 for 4 hr gives (A) along with the isomeric dimers (B) and (C) (Scheme 30). " ... 

Muconic acid has been obtained in a variety of ways. The procedures that seem most important from a preparative point of view are by treatment of ethyl o ,5-dibromoadipate with alcoholic potassium hydroxide, by condensation of glyoxal (as the sodium bisulfite addition product) with malonic acid, by heating ethyl l-acetoxy-l,4-dihydromuconate (obtained by condensing ethyl oxalate and ethyl crotonate, acetylating, and reducing),and by oxidation of phenol with peracetic acid. ... 

The same authors (77) also investigated the Michael addition of nitromethane to a,/l-unsaturated carbonyl compounds such as methyl crotonate, 3-buten-2-one, 2-cyclohexen-l-one, and crotonaldehyde in the presence of various solid base catalysts (alumina-supported potassium fluoride and hydroxide, alkaline earth metal oxides, and lanthanum oxide). The reactions were carried out at 273 or 323 K the results show that SrO, BaO, and La203 exhibited practically no activity for any Michael additions, whereas MgO and CaO exhibited no activity for the reaction of methyl crotonate and 3-buten-2-one, but low activities for 2-cyclohexen-l-one and crotonaldehyde. The most active catalysts were KF/alumina and KOH/alumina for all of the Michael additions tested. 

Ethylaminobutyric acid dimethyl amide is dissolved in absolute ether, then the mixture is well cooled and treated drowsy under stirring with crotonic acid chloride. After a stirring reaction mixture is filtered and residue obtained is dissolved in water and treated by potassium hydroxide. The remaining product is finally rectified in high vacuum to give 2-(N-ethyl-crotonylamido)butyric acid dimethyl amide. 

Chromium trioxide, 60, 21 Clemmensen reaction, 60, 111 Copper chloride (CuCl) [7758-89-6], 61, 122 Crotonic acid, ethyl ester, ( )-, 61, 85 18-Crown-6-potassium cyanide complex, 60,129 Crum Brown-Walker reaction, 60, 4 Cuprous chloride, 60, 42, 121 61, 122 CYANIC ACID, PHENYL ESTER [1122-85-6], 61, 35... 

Ethyl crotonate undergoes fast and selective dimerization at 110" in the presence of potassium and a promoter to form the diethyl ester of diacid with a high yield (16). 

Osmium tetroxide is also a catalyst in the oxidation of the double bond by chlorates. Cis addition of hydroxyl groups takes place as is shown by the preparation of cis-l,2-cyclohexanediol from cyclohexene and the formation of the proper diastereoisomeric dihydroxy derivatives of maleic, fumaric, and 4-halocrotonic acids. Silver chlorate is preferred to potassium chlorate in the hydroxylation of crotonic acid. ... 

Benzene Benzoic acid Betol -Lead -Bromine Lead chloride Lead iodide -a-Crotonic acid -Diphenylamine -p-Dibrom benzene Acetic acid -Potassium -Potassium nitrate Laurie acid -Myristic acid... 

Marzinzik and Felder [34] synthesized a 3-cyanopyridine via the reaction of a polymer-bound enone with 3-amino-crotonic acid nitrile derived in a Thorpe reaction from acetonitrile and potassium terf-butoxide (B b, d Fig. 6.22) [26]- The product was obtained in 46 % yield, and with a HPLC purity of 78 %. 

When ethyl 3-(D-mannosylamino)crotonate (110) is heated with acetic acid and potassium acetate in methanol, ethyl 2-methyl-4-(D-amlnno-tetrahydroxybutyl)pyrrole-3-carboxylate (17) is produced, and it can be isolated from the reaction mixture. ... 

A valid criticism of the technique (similar to that mentioned by Lorenz for rat-paw oedema) has recently been made by Gygielman and Robson , who observed that anti-inflammatory activity, determined by the cotton pellet test, of a group of substances derived from liquorice seems to be associated with irritant effects at the site of injection. They proceeded to show that the injection of known irritants such as antimony potassium tartrate and croton oil produces a significant reduction in granulation tissue. Robinson and Robson suggested, in the light of further experiments, that the reason for this is that an anti-inflammatory factor is produced at the site of implantation of the irritant substance. 

Dihalo carbonyl compounds are readily dehydrohalogenated to -halo carbonyl compounds, e.g., 2,3-dibromobutyric acid is converted into 2-bromo-crotonic acid in 90% yield by aqueous potassium hydroxide.61... 

Figure 4.17. Determination of the reaction rate constant for the oxidation of crotonic acid by potassium permanganate, (a) Manifold used (cf. Figs. 4.15c and 4.16). b, c) Absorbancetime response curves actually recorded. The values of the dispersion coefficient Da were obtained by dispersion experiments. All curves in each set of experiments were recorded consecutively from the same starting point (5 ), with an increasing delay time (td - 7, 8, 9, and 10 s, a-d and a -d ) with the stopped-flow period /s = 20 s (additionally, in each series a single run without stop is included), b) KMn04 (C° = 8.54 x lO"" M) in phosphate buffer in absence of crotonic acid, (c) KMn04 (Cli = 8.54 x lO"" M) in phosphate buffer, crotonic acid (C j = 2.10 x lO"" M) in phosphate buffer, stream B. (From Ref 838 by permission of the American Chemical Society).

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