Current Organic Chemistry - Volume 26, Issue 21, 2022

This Special Issue would cover the hot topics on recent synthetic interest in iodine reagents and related chemistry as well as the unique characteristics of hypervalent iodine compounds. The excellent reviews by the experts and eminent researchers engaged in the recent advances, i.e., preparations, reactions, and mechanistic studies of hypervalent iodine compounds, and their utilizations as reagents and organocatalysts in controlled reactions for synthesizing useful organic molecules, such as pharmaceutical compounds and organic materials, are provided in this Special Issue.

The chemistry of hypervalent iodine reagents is now developed as an important tool of synthetic organic chemistry. These reagents play a key role in replacing the toxic heavy metal reagent because of their mild reaction condition and environmentally friendly nature. Mainly, these reagents were known for oxidative properties, but the scope of these reagents is not limited to oxidation reactions. In the past two decades, they have been used as versatile electrophiles in various key organic transformations. Recently, the demand for these reagents has increased drastically for green chemistry, mainly due to their application in catalysis. Hypervalent iodine reagents have been successfully used to develop various oxidative transformations such as the oxidation of different organic species, α-functionalization of carbonyl compounds, cyclization reactions, C-H activation reactions, lactonization and oxidative rearrangements. Moreover, the use of these reagents is not limited to general organic reactions but is successfully used to develop several stereoselective transformations by using chiral hypervalent iodine reagents. This review article highlights various acyclic and cyclic reactions where the hypervalent iodine reagents have been used as electrophiles.

In the past few decades, the chemistry of hypervalent iodine reagents has undergone a flourishing development in synthetic organic chemistry owing to their mild oxidative, low toxicity, air and moisture stability, and environmentally benign features. A plethora of oxidative coupling reactions have been conducted using hypervalent iodine reagents as nonmetallic oxidants. In particular, the C-S and C-Se bond-forming reactions mediated by hypervalent iodine reagents have emerged as a powerful approach in the construction of Scontaining and Se-containing heterocycles or building blocks. In these reactions, hypervalent iodine reagents behave as strong oxidants or electrophiles and activate the S-containing or Secontaining species to form more electrophilic cationic or radical intermediates, which participate in subsequent coupling reactions. It is anticipated that this review summarizes all C–S and C-Se bonds forming reactions enabled by hypervalent iodine reagents under metal-free conditions.

Iodine(III) reagents represent nowadays a class of highly relevant oxidants in organic synthesis which possess important properties such as safer, non-toxic, green and easy to handle compounds. These characteristics, in several cases, make them important alternatives to the procedures which use hazardous and strong reaction conditions. Based upon their ability as oxidants, they have been exploited in the functionalization of the different aromatic nuclei, allowing the introduction of several groups: among them, inorganic functionalities. Herein, the most relevant developed protocols for functionalizing a broad amount of aryls, heteroaryls and olefins are summarized by introducing the inorganic groups cyano, azido, nitro, sulfur and selenium, using different iodine(III) reagents.

Background: Edifice of C-N bond attained a very impressive position in organic synthesis as it unlocks avenues for offering nitrogen in organic molecules. As we know that water has emerged as a versatile solvent for the synthesis of a variety of organic compounds. Moreover, in accordance to green chemistry, using a very optimistic environment friendly solvent is the main concern for synthetic chemists. Thus, water always comes first in mind as a solvent of choice in appeal to environmentally benign solvents. The inertness of water and its property to dissolve maximum number of compounds, its abundant sources in nature, further embrace it as a crown. Recent years witnessed advancement in green chemistry, further forcing the organic chemists for selecting the solvent for the reaction, which will be less perilous for the mother nature. Material and Methods: Thus, in present time, many reports have been available in literature, wherein water is embellished for performing organic reactions and synthesis of an ample amount of heterocyclic compounds. Therefore, there is a need of time to compile the latest research articles wherein water has been working as solvent to focus on C-N bond forming reactions. As among the heterocyclics, the compounds with carbon nitrogen bonds also possess a significant place due to their importance in medicinal and material science. Results: Thus, the present draft perceived some current and most impressive carbon-nitrogen bond forming reactions exploring water as a reaction media. Moreover, we have made efforts to include more application parts and synthesis of important biological nitrogen containing heterocyclic to be included in the present study. Conclusion: Thus, we have tried here to compile all the recent reports of C-N bond foration in water, which help the reviewers to have insight in to C-N bond forming reactions employing water as reaction media.