Synthesis of New Aryl and Heteroaromatic Substituted Pyridines, Pyrazoles, Pyrimidines and Pyrazolo[3,4-D]pyridazines

The Behavior of 3-Anilinoenone and N-Phenyl Cinnamamide toward Carbon Nucleophiles: Spectroscopy and X-Ray Studies Reveal Interesting New Synthesis Routes to Nicotinonitriles and Tetrahydropyridine-3- Carbonitrile

“…The mass spectra of these compounds revealed a molecular ion peak (M + ) with a m/z value of 230 and 214 respectively. These masses are compatible with the molecular ion peak (M + ) for C 12 H 10 N 2 SO and C 12 H 10 N 2 O 2 respectively as described previously [24]. The complete assignment of 1 H and 13 C chemical shift for 15a are presented in Figure 8.…”

“…Due to their biological activities and pharmacological properties, pyridines and pyridones represent an important class of compounds that have been developed using functionally substituted enaminones [16][17][18][19][20][21][22]. In continuation of our interest in the synthesis of functionally substituted heteroaromatic compounds such as pyridines and pyridones, utilizing enaminones as starting materials [22][23][24][25][26][27][28][29][30][31][32][33], we report here the behavior of 3-anilinoenone and N-phenyl cinnamamide derivative toward malononitrile in the synthesis of pyridine derivatives. The 3-anilinoenone derivative 2a have been used previously, by Al-Saleh et al [19].…”

Microwave Assisted Condensation Reactions of 2-Aryl Hydrazonopropanals with Nucleophilic Reagents and Dimethyl Acetylenedicarboxylate

“…Preparation of 2-arylhydrazono-3-oxo-3-substituted-propanals 6a-h [15] A cold solution of aryldiazonium salt (10 mmol) was prepared by adding a solution of sodium nitrite (1 g in 10 mL H 2 O) to a cold solution of aryl amine hydrochloride (10 mmol of aryl amine in 5 mL concentrated HCl) with stirring as described earlier [15]. The resulting solution of the aryldiazonium salt was then added to a cold solution of enaminone in EtOH (50 mL) containing sodium acetate (1g in 10 mL H 2 O).The mixture was stirred at room temperature for 1h and the solid product thus formed was collected by filtration and crystallized from the appropriate solvent.…”

“…We report herein on the synthesis of iminoarylhydrazonopropanone, azolopyrimidine and 3-oxaloalkanonitrile derivatives of potential interest as pharmaceuticals and photochromic dyes [9][10][11][12][13], starting from enaminones. It has been reported that methylalkyl ketones and methylaryl ketones condense readily with dimethylformamide dimethylacetal (DMFDMA) to yield enaminones, whose chemistry has recently attracted considerable interest [5,6,[12][13][14][15][16][17][18][19][20]. The chemistry of 2-arylhydrazonopropanals has also received considerable interest in the last few years [21][22][23][24][25].…”

Enaminones as building blocks in organic syntheses: on the reaction of 3-dimethylamino-2-propenones with malononitrile

“…[11][12][13][14][15] Sometime ago we reported that enaminones 1 react with malononitrile in refluxing ethanolic sodium ethoxide solution to yield alkoxypyridines 2. 16 However, it was subsequently noted that in ethanolic piperidine solution compound 3 was produced. 17 Recently Kappe et al 18 reported a 1,4-addition of malononitrile to enaminones using microwave heating.…”