Formylacrylic acid

With the saturated analogs, i.e. succinic anhydride and its derivatives, pyridazines are formed in only a few cases. The reaction has been applied to the preparation of perhydro-pyridazines and their 3,6-diones (68MI21200, 70JOC1468). For the synthesis of 4,5-dihalopyridazinones, /3-formylacrylic acids, for example mucochloric acid, are useful syn-thons (Scheme 80). 

B-formylacrylic acid and furan-2-carboxylic acid. Distd over an oil bath from 7% (w/w) Na2CO3 (added to neutralise acids, especially pyromucic acid). Redistd from 2% (w/w) Na2CO3, and then, finally fractionally distd under vacuum. It is stored in the dark. [Evans and Aylesworth lECAE 18 24 7926]. 

The compound was obtained by Yanovskaya, Stepanova and Kucherov [17] from formylacrylic acid ester and nitromethane. No information was given on the possible polymerization of the compound. 

The extensively used synthesis of pyridazines from 3-formylacrylic acids or esters has been extended to many new products. " Mucochloric acid and hydrazine give compound 18 directly or as a by-product on hydrolysis with dilute alkali, 18 gives 19. Transformations of some nitrophenyl-hydrazides of maleic acid into nitrophenylaminomaleimides or pyridazines were studied. ... 

It is produced by the reaction of (a,a,a-trifluoro-w-tolyI)hydrazine with (Z)-2,3-dichloro-3-formylacrylic acid and the coupling of the product with dimethylamine. 

B6I0W, Sicherer, Ber, 1901,84, 3891. Formylacrylic Acid Maleic aemualdehyde) HCCOOH HC-CHO... 

Formylacrylic acid, KGN, and NaHG03 in methanol refluxed 1 hr. with stirring monomethyl succinate. Y 90%. — Reaction in water gives succinic acid. V. Franzen and L. Fikentscher, A. 623, 68 (1959). 

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