Mini-Reviews in Organic Chemistry - Volume 21, Issue 5, 2024

Natural products with oxa-bridged medium-sized carbocyclic ring structure units play an important role in nature. Therefore, developing novel and efficient methods is essential for synthesizing complex natural products containing oxygen-bridged rings. In this article, progress toward the synthesis of oxygen-bridged seven and eight-membered rings is reviewed in terms of the strategies employed.

Nitriles are employed in many academic and industrial fields, especially organic synthesis. They are crucial precursors to synthesize aldehydes, amines, amides, carboxylic acids, and tetrazoles. There are many routes to synthesize nitriles from various species such as aldehydes, alcohols and amines. This review summarized the recently developed direct conversion of aldehydes to nitriles, focusing on the simple and efficient reaction.

It was previously reported that azo compounds are vigorous and chemically stable compounds and well-known chromophores. Having different chromophores, the azo dyes act as probing units for capturing the charged particles either by electron transfer or deprotonation mechanisms. The probing efficiency usually exhibits in the magnitude of variations in UV absorbance, NMR peaks and visually observed color changes. The sensing application is a prerequisite for numerous analytical techniques involved in pharmaceutical as well as pathological discipline. In the last two decades, numerous azo based sensors have been developed, which render low cost and effective sensing approaches towards ionic diagnosis through instantaneous eye beaming chromogenic change. This sensing approach is simple, cost-effective, and precise and provides reliable quantitative and qualitative statistics of an analyte present in a complex environment. Our present study culminates the recent progress on the synthesis of azo compounds and their chromogenic sensing application towards various reactive analytes through reviewing spectral variations and colorimetric observations. This review article assesses the potential of azo dyes in chromogenic sensing for different analytes. We believe this review will be of interest and important for researchers working on designing azo-based chromogenic sensors.

In this review, numerous thieno[2,3-c]quinoline derivatives (TQs2, 3-c) are presented from a variety of angles, including various preparation and processing techniques, using cutting-edge equipment. Numerous chemical processes in this review demonstrate how (TQs2, 3-c) were made from arylamines, ketones, aldehydes, carboxylic acids, and other chemical reagents. The amidation, tandem C-C and C-N bond creation accelerated by palladium, Vilsmeier reaction, and Pictet-Spengler chemical reactions were used to shed light on how (TQs2, 3-c) was made.

This review described the preparation of 2-(piperazin-1-yl) quinoline derivatives from 2- haloquinolines and anilides, which underwent alkylation, arylation, acylation, and reductive amination to form the 2-piprazinoquinolines. 2-(Piperazin-1-yl) quinoline used as building blocks for the synthesis of polyfunctionalized heterocyclic compounds with pharmacological interest.

Among the many zinc salts that can be found, zinc acetate is one of the readily available, affordable, low-hazardous Lewis acids. It can be referred to as a multifunctional catalyst due to its unique physical and chemical properties, which show that they are effective in enabling a variety of synthetic transformations in both organic synthesis and catalysis. This review included noteworthy innovations that have been created during the past two and half decades using zinc acetate as a catalyst or reagent.