Transformations of Alkynes under Metal-Catalyzed and Thermal Reaction Conditions

The following thesis involves four projects in two major areas. In the first part, we describe the intramolecular alkyne carboxyaminations via the N–O bond cleavage strategy. The carboxyamination products generated from alkyne-tethered N-acyloxycarbamates, O-acyloxyhydroxamates or oxime esters undergoes different isomerization processes: π-bond migration, O→N, and O→O acyl group migrations. Therefore, a wide variety of nitrogen-containing heterocycles could be synthesized. In the second part, a recent study of Myers-Saito cyclization is described. The reactivity profile of α,3-dehydrotoluene intermediate is found to be relevant to the reaction counterpart. An acid-mediated benzannulation with nucleophiles incorporated into the aromatic ring is reported as a complement to conventional Myers-Saito cyclization for its opposite regioselectivity.