Synthesis of Fluorescent 2,6‐Dicyano‐3,5‐Disubstituted Anilines Using Cellulose Sulfuric Acid in Aqueous Media

Abstract

The synthesis of some fluorescent 2,6‐dicyano‐3,5‐disubstituted anilines using cellulose sulfuric acid (Cellulose‐SA) as an environmentally benign catalyst in H2O is described. The one‐pot reaction of 1,3‐diketone and three equiv. of malononitrile was carried out in the presence of one equiv. of a secondary amine, Cellulose‐SA as catalyst, and H2O as solvent. The photophysical properties (λAbs., λFlu.) of the synthesized compounds in CH2Cl2, MeCN, and MeOH have been measured. The emission spectra of the new compounds in the solid state are also reported.

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

“…At the same time, the compounds containing 2,6-dicyanoaniline scaffold exhibit various biological activities [ 53 , 54 , 55 ], strong fluorescence [ 55 , 56 , 57 , 58 , 59 ] and may be used as nonlinear optical materials [ 55 , 60 , 61 ] and cell imaging agents [ 55 , 62 ] ( Figure 1 ). Furthermore, they serve as building blocks for the synthesis of diverse biologically active compounds and a large number of heterocyclic derivatives, including indoles, quinazolines, fluorenones, indazoles, benzoxazines and benzotriazinones [ 55 ].…”

Facile Access to Challenging ortho‐Terphenyls via Merging Two Multi‐Step Domino Reactions in One‐Pot: A Joint Experimental/Theoretical Study

“…[15] Combination of an organocatalyzed domino reaction with a metal-catalyzed domino reaction in a sequential one-pot procedure may even further reduce waste, costs and time compared to a classical route of synthesis. [16] While a few organocatalytic or one-pot approaches towards meta-terphenyls have been reported, [17] only one organocatalytic method [3b] and one base catalyzed route [18] towards orthoterphenyls have been established, leading to substituted cyanoaniline derivatives (Scheme 1a,b). Even though these methods provide highly functionalized ortho-terphenyls, major drawbacks are restricted versatility, small scope of substrates, poor yields and requirement of complex starting materials (Scheme 1a,b).…”

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

“…The reported synthetic methods for 2,6‐dicyanoanilines include i) three‐component reactions of aldehydes, ketones and malononitrile; ii) reactions of chalcones with malononitrile in guanidinium ionic liquids; iii) three‐component reactions of α,β‐unsaturated imines with malononitrile; iv) reactions of aldehydes, β‐nitroolefins and malononitrile catalyzed by DMAP; v) reactions of 1,3‐diketones with three equiv. of malononitrile in the presence of a secondary amine . However, these methods have several shortcomings, such as low atomic utilization, harsh reaction conditions, poor substrate suitability, excessive reaction substrates, and low yields, etc.…”

“…of malononitrile in the presence of a secondary amine. [8] However, these methods have several shortcomings, such as low atomic utilization, harsh reaction conditions, poor substrate suitability, excessive reaction substrates, and low yields, etc. These facts further prove that the development of a simple and effective synthetic method for 2,6-dicyanoanilines using suitable materials will be a significant task.…”