Insertion of Arynes into Bonds

摘要

It is well known that the high strain created by the formal triple bond of arynes makes these compounds powerful electrophiles.[1] The addition of a nucleophile X to benzyne leads to the formation of an aryl carbanion that can be trapped with an electrophile Y. If X and Y belong to the same molecule, with a bond between them, the overall process is usually the formal insertion of the aryne into the XY bond (Scheme 1). If X and Y are linked by multiple bonds, a formal [2+2] cycloaddition can result in the formation of a four-membered ring, which in some cases can be opened to obtain the insertion product.