Cyanoacetic acid is a versatile and convenient intermediate for the synthesis of wide variety of heterocyclic compounds. It is mainly used as the basic raw material for cephalosporin acetonitrile, important for medicine and dye intermediates. The Molecular Formula is C3H3NO2,Molecular Weight is 85.06, and CAS NO. is 372-09-8. Cyanoacetic acid is hygroscopic white crystals, melting point 68 ?. Decomposition at 160 ? to carbon dioxide and acetonitrile. Dissolved in water, ethanol and ether, slightly soluble in benzene and chloroform. Cyanoacetic acid was obtained by careful addition of hydrazine hydrate to ethyl cyanoacetate in ethanol with stirring at 0°C.It is produced in a sequence of reactions in which an aqueous solution of chloroacetic acid neutralized with sodium carbonate or sodium hydroxide to form sodium chloroacetate which, in turn, is reacted in a nucleophilic substitution with an alkali metal cyanide and the resultant cyanoacetate is then acidified to form an aqueous reaction mixture comprising this drug and the respective salts formed in such reaction sequence. The reactions of cyanoacetic acid with numerous reagents are classified separately in one category due to the huge number of references. We have arranged this huge volume of data in terms of the type of the heterocycles formed, starting with five and six membered rings in order of increasing number of heteroatoms. Such systematic treatment provides a clear idea about the synthetic possibilities of the method and may be useful in selecting the direction of further research. General procedure for the reaction of cyanoacetic acid with benzal-4-acetylanilines. Benzal-4-acetylaniline/its derivative (1a–10a) (0·01 mol) was taken in dry benzene (20 ml) in a conical flask (100 ml). Then cyanoacetic acid (0·01 mol) and a few drops of pyridine were added to the above solution. The reaction mixture was heated and shaken briskly for 20 min. The flask was then cooled, stoppered and allowed to stand at room temperature for 24 h. when a crude solid separated out which was filtered and recrystallized from benzene to get pure benzalcyanoacetic acid/its derivative (1b–10b).Condensation of cyanoacetic acid with benzal-4-acetylanilines (1a–10a) in 2 :1 molar ratio was also carried out by following the above procedure. Condensation of cyanoacetic acid with benzal-4-acetylanilines (1a–10a), the compounds synthesized by reaction of 4-aminoacetophenone with benzalde-hyde and substituted benzaldehydes (1–10), in equi-molar ratio in the presence of pyridine yielded crude solids (1b–10b) which were purified by recrystalli-zation from benzene. Cyanoacetic acid reacted with carbon–nitrogen dou-ble bond of benzal-4-acetylanilines onlyleaving carbon–oxygen double bond, considered to be more reactive, intact under the reaction conditions. Thus condensation of cyanoacetic acid is a chemoselec-tive reaction with benzal-4-acetylanilines. 4-Methoxybenzalcyanoacetic acid (4b) was found to be most potent among the test compounds against A. alternata , C. capsici and F. oxysporum with ED50 value of 170, 72 and 170 ppm, respectively. The most effective compound against M. roridum and U. tritici was 4-chlorobenzalcyanoacetic acid (2b) and benzalcyanoacetic acid (1b) respectively with ED50value of 70 and 170 ppm. Introduction of nitro-substituent in the phenyl ring of benzalcyanoacetic acid resulted in sharp decline in the fungitoxicity of the parent compound. Thus, the nitro-substituted derivatives (9b,10b) possessed ED50 values of more than 1000 ppm against the test fungi in most of the cases. Want to learn more information about Cyanoacetic acid, you can access the guidechem.com. Guidechem.com is just a place for you to look for some chemicals. Guidechem provide the most convenient conditions for the international buyers and let these leads benefit all the business people.
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