Recent Advances in Diversity Oriented Synthesis through Isatin‐based Multicomponent Reactions

Abstract

Isatins are well‐known carbonyl electrophiles which allow a vast number of reactions initiated by nucleophilic attack on the C3 carbonyl group when used as starting materials. The most notable feature of isatins is that they serve as donors of oxindole fragments and furnish spirocyclic products in most cases. Because of their high reactivity and easy availability, isatins have been broadly used as building blocks in the synthesis of structurally complex and diverse heterocyclic compounds in multicomponent reactions (MCRs). Recent advances in diversity oriented synthesis with isatin‐based MCRs are discussed in this Focus Review and are classified into different sections based on the key transformation involved in the reactions, such as 1,3‐dipolar cycloaddition, Knoevenagel reaction, ring‐opening of isatins and so on.

Boric acid-catalyzed multi-component reaction for efficient synthesis of 4H-isoxazol-5-ones in aqueous medium

“…These reactions have a particular importance in the synthesis of biologically active compounds and natural products due to their significant features such as high efficiency, minimization of waste, versatility, facial completing, atom economy, and excellent functional group compatibility. Also, MCRs in water can be visualized as a well-designed synthetic method to attain a wide range of diverse molecular frameworks [1][2][3].…”

Recent applications of isatin in the synthesis of organic compounds

“…17 Synthesis of spiro 18 and multispiro 19 heterocyclic compounds from isatin were studied by Borad et al The enantioselective reactions of isatin were also the subject of several review articles. [20][21][22] Herein, in continuation of our studies towards isatin, [23][24][25] and since there is a wide range of reactions that include isatin in the synthesis of organic compounds, this review presents the recent applications of isatin in the synthesis of different types of organic compounds up to June 2016.…”

Synthesis of spiro-fused heterocyclic scaffolds through multicomponent reactions involving isatin

“…For example, spirotetrahydro β-carboline is amenable to a single or low dose oral treatment for malaria, Isatin and its derivatives accomplish various reactions for the synthesis of organic compounds; Schiff bases of isatin are used for their pharmaceutical properties 17 and spirooxindoles have significant biological activities. 18,19 The chemistry of isatins was reviewed for the first time by Sumpter 20 and later updated by Popp 21 and da Silva et al 22 In recent years isatin-related review articles have been published on enantioselective reactions with isatin, [23][24][25] biochemical and pharmacological characterization of isatin and its derivatives, 26 isatins as privileged molecules in design and synthesis of spiro-fused cyclic frameworks, 27 recent progress on routes to spirooxindole systems derived from isatin, 28 synthesis of spiro 29 and multispiro 30 heterocyclic compounds from isatin, the use of water in the synthesis of isatin based spirocyclic compounds, 31 and synthesis of heterocyclic compounds based on isatin through 1, 3-dipolar cycloaddition reactions. 32 Considering the importance of isatin as a building block in organic synthesis, and since there is a wide range of reactions that include isatin in the synthesis of heterocyclic compounds, this review gives an overview of the synthesis of different types of spiro-fused heterocyclic scaffolds through multicomponent reactions from the year 2012 to 2015 in which one of the starting materials is isatin.…”