Alkynes aminomercuration-demercuration

There are several methods available for the electrophilic addition of hydrogen and nitrogen to alkenes, dienes and alkynes. While the direct electrophilic addition of amines to these substrates is not feasible, aminomercuration-demercuration affords a very useful indirect approach to such amines. The addition of amides to C—C multiple bonds can be effected directly through the Ritter reaction or by the less direct, but equally useful, amidomercuration-demercuration process using either nitriles or amides. Similarly, H—N3 addition to alkenes can be carried out directly or via mercuration to produce organic azides. 

The aminomercuration-demercuration of alkynes affords a variety of nitrogen-containing products. Most commonly imines are formed,194 though there are a few examples of enamines being produced (equation 163).223-228... 

The addition of amines to electrophilic alkynes and allenes to give enamines is well known221222. It is possible to prepare the F-isomer in a pure state by a stereospecific addition of an amine to an alkyne (equation 10). Enamines have also been obtained by an aminomercuration-demercuration sequence involving addition of aromatic amines to the substituted carbon of unactivated terminal acetylenes 223-225 (equation 11). 

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