Synthesis of heterocyclic compounds. II. A simple one‐step synthesis of pyridines from aldehydes and malononitrile

Abstract

The condensation of several aldehydes with malononitrile in the presence of a alcohol‐alkoxide system provides a new simple, one‐step route to 4‐substituted 2‐amino‐3,5‐dieyano‐6‐alkoxy‐pyridines. The best results are obtained with the aromatic aldehydes. The structure of these compounds was established from a study of their infrared, ultraviolet and nuclear magnetic resonance spectra.

Synthesis of Some New Polyfunctionalized Pyridines

“…11, 83.32, finally, the other aromatic carbons are characterized by peaks at δ 116. 57, 120.82, 130.20, 152.00, 161.19, 161.94, and 166.60 ppm. There are many reported procedures for the synthesis of 2-amino-6-alkoxy-4-arylpyridine-3,5-dicarbonitrile 4 via multi-components reaction between aldehyde and two equivalent moles of malononitrile [17][18][19][20], but there is not anyone for synthesis of their positional isomer 4amino-6-alkoxy-2-arylpyridine-3,5-dicarbonitrile 7. While searching for possible synthesis of 4-amino-6-alkoxy-2arylpyridine-3,5-dicarbonitrile 7, we found out that 2aminoprop-1-ene-1,1,3-tricarbonitrile 5 has not been previously studied in such reactions.…”

“…Yield (Method A, 50%; Method B, 56%); mp 200–202°C (reported 199–200); FTIR (cm −1 ) 3412, 3338, 3238, 2967, 2935, 2212, 1650; 1 H NMR (400 MHz, DMSO‐ d 6 ) δ 7.90 (s. br., 2H, NH 2 ), 7.49 (d, j = 8 Hz, 2H, 2CH arom.…”

Synthesis of 2, 6-Diaryl-4-5-Secondary aminonicotinonitriles as potent antimicrobial agents

“…The condensation of 1,5diketone with ammonia followed by nitric acid oxidation is a common approach for the synthesis of pyridines [15]. The reaction of dienamine and ketone in the presence of Vilsmeier type 1-substituted-1,2,3-benzotriazole reagent results in the formation of nicotinonitriles [16]. The construction of unsymmetrically substituted pyridines was achieved by the reaction of 1,3-dicarbonyl compounds and 3-aminoenones or nitriles [17].…”

Facile synthesis of 2,6‐diaryl‐4‐secondary aminonicotinonitriles and highly substituted unsymmetrical 2,2′‐bipyridines

“…The condensation of 1,5‐diketone with ammonia followed by nitric acid oxidation is a common approach for the synthesis of pyridines [10]. The reaction of dienamine and ketone in the presence of Vilsmeier type 1‐substituted‐1,2,3‐benzotriazole reagent results in the formation of nicotinonitriles [11]. The construction of unsymmetrically substituted pyridines was achieved by the reaction of 1,3‐dicarbonyl compounds and 3‐aminoenones or nitriles [12].…”