p-Toluene Sulfonic Acid-Catalysed Microwave Synthesis of Symmetrical Bisamides by Reaction between Aromatic Aldehydes and Amides

Abstract

Reaction between aldehydes and amides catalysed by p-toluene sulfonic acid in microwave conditions provided a simple and efficient one-pot route for the synthesis of symmetrical bisamide derivatives in excellent yields.

An Efficient Synthesis of Symmetrical Bisamides Catalysed by Molecular iodine under Neutral Conditions

“…All the physical and spectroscopic data of the known compounds were in agreement with those reported in the literature 6,8,9,11,12 . Compounds 3i, 3j, 3k and 3u were new, and their structures were deduced by elemental and spectral analysis.…”

“…1 They can be easily transformed into other useful materials such as gem-diaminoalkyl and aminoalkyl groups and are of considerable interest in the synthesis of pharmacological substances such as peptidomimetics. [2][3][4][5] Bisamides are usually prepared by the direct addition of the corresponding amides to aldehydes in the presence of protic catalysts such as triflic acid, 6,7 p-toluenesulfonic acid, 8,9 phosphotungstic acid 10 or by the reaction of aldehydes with nitriles catalysed by chlorosulfonic acid. 11 Bisamides have also been prepared by the reaction of an alkyne, an aromatic aldehydes and an amides in the presence of SiO 2 -BaCl 2 .…”

Microwave-Assisted Protection of Primary Amines as 2,5-Dimethylpyrroles and Their Orthogonal Deprotection

“…We assumed that nucleophilic attack of the primary amino group in 1 (Scheme 1) on the activated carbonyl in 2 could be accelerated by employing microwave irradiation. Because microwaves are known to accelerate a variety of organic reactions in toluene, 17 and microwaveassisted reactions with p-toluene sulfonic acid have been reported, 18 we decided to determine the efficiency of microwaves to reduce the reaction time for protection of 1 with 2 (Scheme 1). The overall sequence required the addition of the primary amine (1 equiv), acetonylacetone (1.2 equiv), and p-toluene sulfonic acid (0.1 equiv) to toluene in a sealed microwave reaction vessel.…”

Solar-Assisted Green Synthesis, Molecular Docking, Antibacterial, and Cytotoxicity Studies of Symmetrical N, N’-Alkylidene Bisamides Bearing Lower E-Factors

“…In literature, several methods have been reported for synthesizing symmetrical N, N′ alkylidene bisamides. In general, conventional heating, ultrasound [26], and microwave [27,28] have been associated with the synthesis of N, N′ alkylidene bisamides in the presence of different metal catalysts [29,30], Lewis or Bronsted acids [31][32][33][34][35][36][37][38][39], ionic liquids [40][41][42], graphene oxide [43], CC-activated DMSO [44]. However, implementing these methods is not environmentally friendly due to the extensive use of expensive and toxic reagents, metal catalysts, hazardous organic solvents, and reaction conditions.…”