Insertion of Arynes into a Bonds

摘要

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