Three‐Component Domino Reaction in PPG: An Easy Access to 4‐Thiazolidinone Derivatives

Abstract

A simple, economical, and convenient synthesis of a new series of 4‐thiazolidinone derivatives using one‐pot three‐component condensation of aromatic amines, thioglycolic acid and aromatic aldehydes or cyclohexanone in polypropylene glycol (PPG), a recyclable and inexpensive solvent medium is reported. All the reactions are carried out at 110°C without using catalyst or additives. The products are obtained in good to excellent yields (60–97%) after easy workup and purification.

Facile Multicomponent Mannich Reaction towards Biologically Active Compounds

“…It has also been modified by a number of ways. The coupling of aldimines with silyl enol ether, [18] reaction of aldimine with fluorovinyl ether, [19] reaction of chiral aldimines with silyloxydienes, [20] along with reaction of fluorinated aldimines and aliphatic aldehydes [21] are some crucial variations. The multi‐component Mannich reaction includes reaction of cyclic iminium ions with enol compounds [22] which has been extended with annulated N ‐alkoxycarbonyl pyrrolinium ion with 2‐trimethylsilyloxyfuran, coupling between optically active N ‐acylhydrazones with hydrazones, silyl enolates, [23] along with ketene silyl acetal, [24] as well as reaction between hydrazone ester with silicon enolates, combination of α ‐imino ester with aldehydes, and reaction of α ‐imino glyoxylate with α , α ‐difunctionalised aldehyde [25] .…”

Sulfamic Acid-Catalyzed One-Pot Room Temperature Synthesis of Biologically Relevant Bis-Lawsone Derivatives

“…Implementation of several transformations in a single manipulation in a MCR strategy offers a handful of advantages, particularly a facile automation, operational simplicity, reduction in the number of workup steps, thereby minimizing the extraction and purification processes as well as waste generation, and savings of energy and manpower. All these issues are directly linked with the goals of “green and sustainable chemistry”. − In addition, designing for room temperature conditions coupled with other green aspects is also an area of current choice in synthetic organic chemistry …”

Facile and One-Pot Access of 3,3-Bis(indol-3-yl)indolin-2-ones and 2,2-Bis(indol-3-yl)acenaphthylen-1(2H)-one Derivatives via an Eco-Friendly Pseudo-Multicomponent Reaction at Room Temperature Using Sulfamic Acid as an Organo-Catalyst

“…In recent times, multicomponent reactions (MCRs) have gained eminence as a synthetic tool for producing structurally complex molecular entities with attractive biological features through the formation and breakage of several carbon–carbon and carbon–heteroatom bonds in one pot. − It is becoming increasingly important both in academia and in industry to design less toxic and more environmentally friendly MCRs. In addition, implementation of several transformations in a single manipulation in the MCR strategy is highly compatible with the goals of sustainable and “ green ” chemistry. , As part of our continuing efforts to develop green synthetic methodologies for useful organic transformations, − herein, we wish to report a straightforward, efficient, clean, and high-yielding one-pot pseudo-multicomponent reaction protocol for synthesis of a series of functionalized 3,3-bis­(indol-3-yl)­indolin-2-ones ( 3 ) and 2,2-di­(1 H -indol-3-yl)­acenaphthylen-1­(2 H )-ones ( 5 ) from the condensation reaction between different indoles and a variety of isatins/acenaphthaquinone in aqueous ethanol at room temperature using commercially available sulfamic acid as the inexpensive, reusable, and environmentally benign organo-catalyst.…”