1-Substituted 3-Dimethylaminoprop-2-en-1-ones as Building Blocks in Heterocyclic Synthesis: Routes to 6-Aryl- and 6-Heteroaryl-2H-pyran-2-ones and 6- and 4-Arylpyridin-2(1H)-ones

About the reaction of β‐dimethylamino‐α,β‐enones with active methylene nitriles

“…Thus, the enaminone compounds 1a-c were prepared and allowed to react with the active methylene compounds 2a,b according to the method and under the same reaction conditions reported by Elnagdi and coworkers [12]. In our hands, we could isolate the 2-cyano-5-dimethylamino-5-arylpenta-2,4-dienoic amide derivatives 8a-c from the reaction of 1a-c with malononitrile 2a.…”

“…The reaction of enaminones with active methylene nitriles represents one of the strategies for the preparation of 2-1H-pyridone [9][10][11]. 3-Dimethylamino-1-arylpropenones 1a-c have been extensively used in the last years by Elnagdi and coworkers for the synthesis of pyridones [12][13][14]. The reaction of 1a-c with active methylene nitriles (namely malononitrile 2a and cyanoacetamide 2b; Scheme 1) in all these and other publications was based on the idea of a Knoevenagel condensation of the active methylene in 2a or 2b with the carbonyl groups of 1a-c.…”

“…The reaction of 1a-c with active methylene nitriles (namely malononitrile 2a and cyanoacetamide 2b; Scheme 1) in all these and other publications was based on the idea of a Knoevenagel condensation of the active methylene in 2a or 2b with the carbonyl groups of 1a-c. In one article, it was assumed that malononitrile 2a is first hydrolyzed to cyanoacetamide by the water present in the solvent [12], which then condenses with the carbonyl group of 1a-c to afford 3a-c. In the other article, it was assumed that the condensation takes place first and then the water resulting from the condensation hydrolyzes one of the cyano groups in the products of 2a but do nothing with the products of 2b to afford the amides 3a-c [13].…”

Facile approach to prepare 3-cyanopyridin-2(1H)-one derivatives

“…The main strategy involves the condensation of β-enaminoderivatives of carbonyl compounds with cyanoacetic acid amides or malononitrile. 5,6 We report herein a new, efficient and convenient synthetic approach to 3-cyanopyridin-2-ones utilizing various ylidenecyanoacetic acid ethyl esters and dimethylformamide dimethyl acetal as starting materials. The reaction was carried out in anhydrous xylene under reflux for 3 hours.…”

Novel thiophene derivatives with sulfonamide, isoxazole, benzothiazole, quinoline and anthracene moieties as potential anticancer agents

“…3-(Dimethylamino)-1-(thiophen-2-yl)prop-2-en-1-one (1) was prepared according to the reported method (34). (10) and (11).…”