Ugi Four-component Reaction (U-4CR) Under Green Conditions Designed for Undergraduate Organic Chemistry Laboratories

Abstract

Multicomponent reactions (MCRs) are a green strategy in which a collection of molecules with a great diversity are generated with a minimum of synthetic effort, time and by-products formation. The Ugi Multi-component reaction is a chemical reaction in which an aldehyde, an amine, a carboxylic acid and an isocyanide react to form a α-bisamide. In this work, we use the Ugi reaction, as an example of MCRs, to approach organic chemistry undergraduate students to sustainable reactions. This reaction can be carried out under on-water or solvent-free conditions, both at room temperature as in combination with microwave irradiation or ultrasound. The advantages and limitations of the usage of Ugi reaction, under these conditions, in an organic chemistry laboratory course are discussed. In this context, we used different parameters to calculate how environmentally friendly the assayed conditions are. The Chemical Manufacturing Methods for the 21st Century Pharmaceutical Industries (CHEM21 project) were used with this objective. The present work could contribute to the teaching of ecofriendly synthetic strategies, demonstrating the scientific and academic benefits of green chemistry.

A Focused Library of NO‐Donor Compounds with Potent Antiproliferative Activity Based on Green Multicomponent Reactions

“…Interestingly, this fact opened a synthetic avenue for the direct access to both series of compounds using a unique set of reactants under a unique set of reaction conditions. In this regard, good values were observed when the “mass efficiency of the reaction” (RME) was calculated for these reactions as shown in Equation : …”

Green Method for the Synthetic Ugi Reaction by Twin Screw Extrusion without a Solvent and Catalyst

“…All the products are reported in the literature. 29,30 The 1 H-NMR and 13 C-NMR spectra were recorded on a 400 MHz Bruker using TMS as the internal reference and CDCl 3 as the solvent. Purity of a compound can be determined by TLC checking.…”

Catalyst-free synthesis of novel 1,5-benzodiazepines and 3,4-dihydroquinoxalines using isocyanide-based one-pot, three- and four-component reactions

“…This results in both economic and environmental benets. [4][5][6][7][8] One of the benets of the isocyanide functional group in MCRs is its unique reactivity; thus isocyanide-based MCRs (IMCRs) are considered amongst the most versatile MCRs to generate diversity and structural complexity. [9][10][11] The use of isocyanides for the synthesis of nitrogen-containing heterocyclic compounds such as benzodiazepines [12][13][14] and quinoxalines [15][16][17][18] is well exploited.…”