ChemInform Abstract: Nitriles in Heterocyclic Synthesis: Synthesis of New Ethyl‐Substituted Polyfunctional Hetero‐Aromatics.

Abstract

Nitriles in Heterocyclic Synthesis:Synthesis of New Ethyl-Substituted Polyfunctional Hetero-Aromatics.-Propylidenemalononitrile, prepared in situ from the corresponding aldehyde (I) and malononitrile (II), reacts with compounds bearing active methylene groups, such as (V) and (VIII), or active hydrogen functions, e.g. (X), to afford novel heterocyclic derivatives. -(ELGHANDOUR, A. H. H.; IBRAHIM, M. K. A.; ALI, F. M. M.; ELSHIKH, S. M. M.; Indian J. Chem., Sect. B: Org. Chem.

Aliphatic aldehydes in the synthesis of carbo- and heterocycles: Part II. Synthesis of six- and seven-membered rings, bicyclic compounds, and macrocycles

“…The condensation of propanal (1a) with malononitrile (13) in the presence of morpholine as catalyst gave previously unknown substituted aniline 14, pre- sumably through intermediates 15-18 [2,3] (Scheme 2). The process involves consecutive Knoevenagel and Michael reactions and intramolecular cyclization.…”

“…The most convenient and efficient synthesis of 4-alkyl-2-amino-3-cyano-4H-pyrans 122 involves consecutive Knoevenagel condensation and Michael addition, followed by intramolecular cyclization [13,[131][132][133][134][135][136][137] (Scheme 42). The process is catalyzed by organic bases (triethylamine, N-methylmorpholine) and alkali metal fluorides.…”

“…Pyridin-2-one derivatives were proposed as a new class of non-nucleoside anti-AIDS drugs. A procedure for the synthesis of substituted pyridin-2-ones and their chalcogen analogs 33 and 34 from aliphatic aldehydes 1a, 1c, and 1f, 1,3-dicarbonyl compounds 35, and CH acids 36 under base catalysis was developed [7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24] Functionally substituted 4-alkyl-6-amino-3,5-dicyanopyridin-2(1H)-ones and -thiones 37 are also convenient building blocks for the synthesis of biologically active compounds [7,13,14,[25][26][27][28]. They are prepared according to Scheme 7.…”