Recent advances in metal catalyzed or mediated cyclization/functionalization of alkynes to construct isoxazoles

Abstract

<p>This review summarized the recent developments in metal catalyzed or mediated cyclization/functionalization of alkynes to construct isoxazoles.</p>

Transition Metal‐Free Synthesis of Carbo‐ and Heterocycles via Reaction of Alkynes with Organylchalcogenides

“…Cyclization reactions of alkynes neighboring nucleophilic substituents at an appropriate position represent an attractive and powerful strategy for the synthesis of carbo‐ and heterocycles. In the last years, several protocols were developed to construct a diverse array of highly functionalized molecules employing noble transition metals as the catalysts [1–4] . More recently, the use of inexpensive iron and copper salts has emerged as reliable tool in generating a wide variety of cyclic compounds [5,6] .…”

“…In the last years, several protocols were developed to construct a diverse array of highly functionalized molecules employing noble transition metals as the catalysts. [1][2][3][4] More recently, the use of inexpensive iron and copper salts has emerged as reliable tool in generating a wide variety of cyclic compounds. [5,6] Despite their promising use, certain reactions often proceed at high temperatures and low regioselectivity.…”

An overview of metal-free synthetic routes to isoxazoles: the privileged scaffold

“…14 Very recently, Li and his group reported the synthetic sequence leading to isoxazoles via the metal-catalyzed cyclization/ functionalization of alkynes. 15 Subsequently, our group demonstrated the microwave-assisted green synthetic pathway for the synthesis of 3,5-disubstituted isoxazoles using a Cu(I) catalyst. 16 It is well known that metal catalysts and organometallic reagents are widely used for academic research as well as industrial purposes.…”

Diorganyl Dichalcogenides and Copper/Iron Salts: Versatile Cyclization System To Achieve Carbo- and Heterocycles from Alkynes

“…[1][2][3] In fact, noble transition-metals such as palladium, ruthenium, and gold have been widely and successfully employed to the synthesis of a variety of carbo-and heterocycles via intramolecular cyclization reactions. [4][5][6] Despite the undeniable importance and applicability of these noble metals, their relatively high cost and the use of drastic conditions in certain protocols have been aroused interest in the use of cheaper and environmentally friendly transition-metal salts. Thus, copper and iron salts have emerged as alternative synthetic tools for the preparation of several organic molecules.…”

“…[1][2][3] In fact, noble transition metals such as palladium, ruthenium, and gold have been widely and successfully employed for the synthesis of a variety of carboand heterocycles via intramolecular cyclization reactions. [4][5][6] Despite the undeniable importance and applicability of Carla K. Jurinic completed the graduation in chemistry at the Federal University of Fronteira Sul (UFFS) in 2017. She obtained a postgraduate degree in Educational Guidance at the UFFS in 2019.…”