Metal Catalyzed vs. Metal Free Sequential (Hydro)amination /Annulation Reactions of 2-Aminoaryl(heteroaryl) Carbonyls with Ynamides

Aminoquinolines represent an important class of bioactive molecules found in various natural products and drugs. [1a] Moreover, they serve as versatile building blocks for the synthesis of more complex heteroaromatic compounds. Various efficient approaches to the synthesis of these compounds are based on the use of ynamides as synthetic precursors. [1b-e] In fact, ynamides exhibit unique reactivity that enables regioselective and chemoselective synthesis of a variety of heterocycles [2]. Their synthetic applications are growing in importance due to the development of practical methods for their preparation. [3] the Based on the previous work on the synthesis of 2-aminoquinolines through Au/Ag catalyzed regioselective hydroamination/annulation of readily available 2 acylaminoanilines with ynamides, [1e] we explored alternative metal catalyzed (including gold, copper, silver, and zinc) vs. metal-free procedures of the corresponding 4-unsubstituted-2 aminoquinolines. The results will be discussed at the meeting.