Gold‐Catalysed Nitroalkyne Cycloisomerization – Synthetic Utility

Abstract

Dedicated to Professor Christian Bruneau for his outstanding contribution to catalysis

Synthesis, characterization, and crystal structure of 2-(2-azidophenyl)-3-oxo-3H-indole 1-oxide

“…Notably, indolone-N-oxides, also known as isatogens, hold substantial importance in medicinal chemistry and serve as intermediates in the synthesis of natural alkaloids and bioactive compounds (Nepveu et al, 2010). The literature contains a wide array of techniques for synthesizing isatogens, encompassing both metal-free and metal-catalyzed routes Dhote, Halnor et al, 2021). These methods have been rigorously explored and well documented, underscoring the adaptability and importance of isatogens in the realms of organic synthesis and medicinal chemistry.…”

Synthesis of Hydroxysuccinimide Substituted Indolin-3-ones via One-Pot Cascade Reaction of o-Alkynylnitrobenzenes with Maleimides under Au(III)–Cu(II) Relay/Synergetic Catalysis

“…Compared with conventional step-by-step synthetic procedures, one-pot cascade reactions are more advantageous in terms of reaction efficiency, atom economy, and operation simplicity . In this aspect, o -alkynylnitrobenzene has been employed as an effective component in a number of one-pot cascade reactions leading to the formation of various fused N -heterocycles. , For examples, Ramana et al have reported a one-pot Au­[III]/Lewis acid cocatalyzed cycloisomerization of nitroalkyne followed by [3 + 3] cycloaddition with donor–acceptor cyclopropane to afford structurally interesting tricyclic pseudoindoxyl scaffold (Scheme a) . Song et al disclosed the construction of C2-tetrasubstituted indolin-3-ones through copper-catalyzed radical difluoroalkylation and redox annulation of nitroalkynes with bromodifluoroacetate (Scheme b) .…”

Regioselective Cross-Coupling of Isatogens with Boronic Acids to Construct 2,2-Disubstituted Indolin-3-one Derivatives

“…1 Consequently, substantial synthetic efforts have been devoted to construct these important molecules. 2−4 These methods could be divided into three main strategies: (1) oxidative dearomatization of indoles, 2 (2) cyclization of preprepared substrates, 3 and (3) nucleophilic additions to 3H-indol-3-ones 4 or indolone-N-oxides. 5 Indolone-N-oxides (also known as isatogens) have important applications in medicinal chemistry, and they can also be used as intermediates to synthesize natural alkaloids or bioactive molecules.…”