Synthesis of 3,5‐Diaryl‐2,6‐dicyanoanilines from Tandem Reactions of Ynones with Malononitrile

Abstract

A new method for the synthesis of 3,5‐diaryl‐2,6‐dicyanoanilines from tandem reactions of ynones with malononitrile in the absence of transition metal catalysts is described. This protocol has good functional group tolerance, mild condition, high yield and simple work‐up procedure.

Substituent-Dependent Divergent Synthesis of 2-(3-Amino-2,4-dicyanophenyl)pyrroles, Pyrrolyldienols and 3-Amino-1-acylethylidene-2-cyanopyrrolizines via Reaction of Acylethynylpyrroles with Malononitrile

“…According to our preliminary experiments, under the abovementioned conditions [ 65 ] (KOH/MeCN, 40 °C, 6 h), the reaction of 1-methyl-2-(benzoylethynyl)pyrrole 1a with malononitrile 2 (the ratio 1a : 2 : KOH is 1 : 2 : 2) did not afford the expected product, the process was accompanied by resinification. Therefore, in order to find suitable conditions for the construction of 1-methyl-2-(3-amino-2,4-dicyanophenyl)pyrrole 3a , we further carried out the reaction of acylethynylpyrrole 1a with malononitrile 2 at room temperature.…”

“…However, these methods have several shortcomings, such as low reaction selectivity or non-mild reaction conditions (reflux in toluene) and the large span of the yields (16–70%). Later [ 65 ], the conditions for the selective formation of 3,5-diaryl-2,6-dicyanoanilines via the same reaction with a yield of up to 87% were found (KOH/MeCN, 40 °C, 6 h) ( Scheme 1 c). However, the substrate scope of this reaction is limited only to aryl and thienyl substituents.…”

Tandem Reactions of Ynones: via Conjugate Addition of Nitrogen‐, Carbon‐, Oxygen‐, Boron‐, Silicon‐, Phosphorus‐, and Sulfur‐Containing Nucleophiles

“…(64‐2)]. In 2019, Li and He described the synthesis of 3,5‐diaryl‐2,6‐dicyanoanilines 64.9 from the tandem reaction of ynones with 200 mol% of malononitrile [Eq. (64‐3)] (Scheme ).…”

A divergent procedure for multicomponent synthesis of novel ferrocenyl derivatives of dicyanoanilines and cyanopyridines

“…Therefore, many research groups have investigated the synthesis of different groups of dicyanoanilines in recent years. [11,12] One of the most studied organometallic species is ferrocene. [13] This is due to relatively high stability and commercial availability [14] (or ease of synthesis) [15] of various ferrocene containing reactants, allowing synthetic chemists to develop diverse methodologies for functionalization of the ferrocene structure.…”

“…Therefore, many research groups have investigated the synthesis of different groups of dicyanoanilines in recent years. [ 11,12 ]…”