Rhodium(III)-Catalyzed C-H Activation of α-Iminonitriles or α-Imino Esters and Cyclization with Acrylates to 2 H-Isoindoles

Copper(II)/DBU Relay Catalyzed Annulation of α-Carbonyl-γ-alkynyl Sulfoxonium Ylides for Accessing N-Sulfonamido 2H-Isoindoles

A copper(II)/DBU relay catalyzed annulation of α-carbonyl-γ-alkynyl sulfoxonium ylides as a new class of sulfoxonium ylide reagents with sulfonyl hydrazides is reported, enabling intramolecular oxygen migration to produce a series of N-sulfonamido 2H-isoindoles with good yields. The present annulation proceeded readily by combining the Cu(II)-catalyzed 6-endo-dig oxo-cyclization with the DBU-catalyzed isochromene skeletal rearrangement, resulting in the formation of multiple new chemical bonds.

Rh(III)-Catalyzed Synthesis of Substituted Isoindoles through a Direct C-H Activation/[4 + 1] Annulation and Acyl Migration Cascade of Oxadiazolones with Diazo Compounds

A Rh(III)-catalyzed C-H bond activation for the synthesis of fused 2H-isoindole scaffolds from oxadiazolones with diazo compounds was developed. The reaction proceeded through C-H activation of oxadiazolones/[4 + 1] annulation, intramolecular cyclization, and an unusual acyl migration cascade to afford target scaffolds with good yields. These 2H-isoindole derivatives could be further transformed into intriguing drug privileged scaffolds.

Ligand-assisted olefin-switched divergent oxidative Heck cascade with molecular oxygen enabled by self-assembled imines

Divergent oxidative Heck reaction has proven to be reliable for the rapid construction of molecular complexity, while olefins switched the outcome that remained underexplored.

Recent Developments in Isoindole Chemistry

Isoindoles are highly reactive aromatic heterocycles that have a variety of important applications in areas such as medicine, analytical detection, and solar energy. Due to their highly reactive nature, isoindoles can be used to access their derivatives, which possess a diverse array of biological activities. However, their reactivity also makes isoindoles unstable and thus, difficult to prepare. Consequently, there has been a need for the development of novel methods that address some of the synthetic challenges and limitations, as well as reactions that utilize isoindoles to access potentially useful compounds. This review will give an overview of the novel reactions reported within the past decade (2012 to 2022) that involve 2H- and 1H-isoindoles and fused isoindoles as reactants, key intermediates, or products. This review is divided into two parts, with the first part focusing on the synthesis of isoindoles and the second part focusing on reactions of isoindoles. The scopes and limitations of the methods described therein will be discussed and the significance of their contributions to the literature will be highlighted. Similar reactions will also be compared.

1 Introduction

2 Synthesis of Isoindoles

2.1 Synthesis of 2H-Isoindoles

2.2 Synthesis of 1H-Isoindoles

3 Reactions of Isoindoles

3.1 Reactions of 2H-Isoindoles

3.2 Reactions of 1H-Isoindoles

4 Conclusions

Rh(III)-Catalyzed [5 + 1] Annulation of Indole-enaminones with Diazo Compounds To Form Highly Functionalized Carbazoles

A novel Rh(III)-catalyzed C-H activation/annulation cascade of indole-enaminones with diazo compounds was reported to construct diversely functionalized carbazole frameworks. The most notable characteristic is that this transformation could smoothly furnish a novel [5 + 1] cyclization product with good to excellent yields (up to 95%), accompanied by the thorough removal of acetyl and N,N-dimethyl groups of two substrates from the target products, rather than the normally expected [4 + 2] cyclization products.

A Rh(iii)-catalyzed C–H activation/regiospecific annulation cascade of benzoic acids with propargyl acetates to unusual 3-alkylidene-isochromanones

We developed a new approach to synthesize isochromanones with benzoic acids and propargyl acetates, which introducing an unusual exocyclic C–C double bond at the 3-position with high regioselectivity and moderate to excellent yields.

Magnetic nanocatalysts utilized in the synthesis of aromatic pharmaceutical ingredients

This review covers recent developments in nanoscale magnetic catalytic systems and their applications in facilitating organic synthetic reactions of aromatic pharmaceutical ingredients.

Rh(III)-Catalyzed Dual C-H Functionalization/Cyclization Cascade by a Removable Directing Group: A Method for Synthesis of Polycyclic Fused Pyrano[de]Isochromenes

An interesting Rh(III)-catalyzed dual C-H functionalization/cyclization cascade of azomethine imine with diazophosphonate by a removable directing group for the synthesis of highly fused pyrano[de]isochromene has been achieved. The transformation shows that the desired pyrano[de]isochromenes with two oxygen atoms on its core scaffold could be constructed with good to excellent yields (up to 86%) via a facile one-pot, multiple-step cascade reaction, along with broad generality and versatility.

Cellulose-Supported Sulfonated Magnetic Nanoparticles: Utilized for One-pot Synthesis of α-Iminonitrile Derivatives

ntroduction: An instrumental strategy for α-iminonitrile derivatives preparation by Fe3O4@cellulose-OSO3H (MCSA) as an eco-friendly nanocatalyst and oxidative agent in aerobic condition, is presented.

MATERIALS AND METHODS

Through this method, a one-pot three-component condensation reaction of various aldehydes, primary amines and trimethylsilylcyanide (TMSCN) were applied to synthesize the desired products. It was performed in absolute ethanol and under a mild condition by using the presented nanocatalyst. High reaction yields were obtained through using the presented magnetic agent, as well. Moreover, the threecomponent reactions were executed using accessible and economical precursors. The convenient separation and recyclability of the used nanocatalyst were also precisely investigated.

RESULTS AND DISCUSSION

In this research, we identified novel α-iminonitrile derivatives using 1H NMR, 13C NMR, CHN, and FT-IR analyses, as well. In order to determine the well-known derivatives, we used FT-IR method as well as comparing their melting points with those of reported.

CONCLUSION

In summary, an extremely efficient method was used for the environmentally-friendly synthesis of α-iminonitrile derivatives that are important bioactive substances. The catalytic oxidative coupling reaction afforded the products via a one-pot three-component condensation reaction of various aldehydes, primary amines and TMSCN with great reaction yields, in ethanol under mild conditions.

Rhodium(III)-Catalyzed Redox-Neutral [3+3] Annulation of N-nitrosoanilines with Cyclopropenones: A Traceless Approach to Quinolin-4(1H)-One Scaffolds

A traceless approach to quinolin-4(1H)-one scaffolds through Rh(III)-catalyzed redox-neutral [3+3] cyclization of N-nitrosoanilines with cyclopropenones has been achieved. This protocol features short reaction time and atom-economical combination without extra additives, which can be further applied in the construction of privileged heterocyclic compounds in pharmaceutical chemistry.

A removable directing group-assisted Rh(iii)-catalyzed direct C–H bond activation/annulation cascade to synthesize highly fused isoquinolines

A removable directing group-assisted Rh(iii)-catalyzed direct C–H bond activation/annulation cascade was developed to synthesize highly fused isoquinolines with good to excellent yields and a good functional group tolerance.

Rh(III)-Catalyzed Coupling of N-Chloroimines with α-Diazo-α-phosphonoacetates for the Synthesis of 2H-Isoindoles

We report herein the first use of N-chloroimines as effective synthons for directed C-H functionalization. Rh(III)-catalyzed coupling of N-chloroimines with α-diazo-α-phosphonoacetates allows for efficient dechlorinative/dephosphonative access to 2H-isoindoles. Further deesterification under Ni(II) catalysis enables the complete elimination of reactivity-assisting groups and full exposure of reactivity of C3 and N2 ring atoms for attaching structurally distinct appendages.