Hydroamieation of Alkynes with Ammonia: Unforeseen Mole of the Gold(I) Catalyst

摘要

The formation of nitrogen-carbon bonds represents a highly valuable synthetic method to prepare products ranging from chemical feedstocks to pharmaceutical materials. It is therefore not surprising that such reactions have been the focus of catalysis research. The use of ammonia as a reactant is highly desired as the addition of NH3 to C-C multiple bonds represents a highly attractive process for C-N bond formation, and complete atom economy is achieved. Nevertheless, atom-efficient processes for combining NH3 with simple organic molecules are rather scarce. It is known that transition-metal complexes can make N-H bonds reactive for additional functionalization, however in most cases when metals react with ammonia (there are some exceptions) the supposedly inert Werner complex is formed. Hence, functionalization of NH3 was difficult to obtain until the groups of Hartwig and Buchwald described the palladium-catalyzed coupling of ammonia with aryl halides.