Hydrolytic Heterocyclization of the 1,1,2,3,3‐Pentacyanopropene Salts

Abstract

in Wiley Online Library (wileyonlinelibrary.com).Salts of 5-amino-4-cyano-3-dicyanomethylene-2-pyrrolinone are formed by action of dilute aqueous solutions of alkalis on pentacyanopropenide-anion salts. These cyclic salts are transformed to 2,6-diamino-3, 5-dicyanoisonicotinates by subsequent action of alkalis.

Synthesis and Solid State Fluorescence of Malononitrile Trimer Ylidene Derivatives in Aqueous Medium under Ultrasonication

“…Compounds containing a 1,1,3,3-tetracyano propenide fragment have attracted much interest due to their great potential for the synthesis of five-and sixmembered heterocycles, including fused ones [1][2][3][4][5], as well as their thermo-and photochromic [6], semiconducting [7], magnetic [6,8], and chemosensory properties [9]. We previously reported the synthesis of potassium (Z)-4-aryl-2-(dicyanomethylidene)-1,1,3-tricyanobut-3-en-1-ides 1 and (3Z,5E)-6-aryl-2-(dicyanomethylidene)-1,1,3-tricyanohexa-3,5-dien-1-ides 2 by Knoevenagel condensation of substituted benzaldehydes [9] and cinnamaldehydes [10] with malononitrile trimer potassium salt 3 in propan-2-ol or in aqueous medium in the presence of surfactants, e.g., Oksipav AP [11].…”

The first example of unusual reversible nucleophilic addition to 2-(5-aryl-2-oxo-3H-pyrrol-3-ylidene)malononitriles – a new tool for the creation of thermosensitive molecular switches

“…23 At the same time, reactions at the C2 atom allowed the synthesis of quinoline compounds 24 from indoles A or their 3-oxo-substituted analogs, 25 as well as hard-to-reach derivatives of isonicotinic acid from pyrroles B . 19,26…”

“…Non-fused pyrrole derivatives B are significantly less available. [18][19][20] According to literature data, compounds A and B are characterized by reactions with nucleophiles at the electrophilic C2 and C3 atoms of the pyrrole ring. Reactions of compounds A and B at the C3 atom led to biologically active spiroindoles 21,22 and spiropyrroles, respectively.…”

“…23 At the same time, reactions at the C2 atom allowed the synthesis of quinoline compounds 24 from indoles A or their 3-oxo-substituted analogs, 25 as well as hard-to-reach derivatives of isonicotinic acid from pyrroles B. 19,26 Despite the structural similarity, the C5 atom of the fivemembered heterocyclic component is a crucial difference between structures A and B. In the case of isatins A, this atom is included in the aromatic system and, therefore, its involvement in reactions with nucleophiles is unlikely.…”