Bestmann–Ohira Reagent: A Convenient and Promising Reagent in the Chemical World

Abstract The Bestmann–Ohira reagent is a unique and versatile reagent in organic synthesis. It is a well‐known homologating agent for the conversion of aldehydes into the corresponding terminal alkynes. Recently, it has also been used as a potent cycloaddition partner in 1,3‐dipolar cycloaddition reactions. The Bestmann–Ohira reagent can be readily accessed from commercially available sources. It has found tremendous application in the regioselective synthesis of a variety of organic synthons, including alkynes, triazoles, triazolines, pyrazoles, oxazoles, thiazoles, isoquinoline N ‐oxides, indazoles, pyrroles, and enol ethers in good‐to‐very‐good yields.