Gold(I) catalysis has experienced a huge development in the past decades. Our research group has focused on the development of powerful gold(I)-catalyzed methods for the synthesis of complex molecular frameworks. In this context, this Doctoral Thesis covers three topics related on the application of homogenous gold(I) catalysis for the activation of acetylene gas, the smallest existing alkyne.

Firstly, the gold(I)-catalyzed aryloxyvinylation reaction of o-allylphenols with acetylene gas was studied in detail. The reaction takes place through the formation of a cyclopropyl gold(I) carbene followed by the intramolecular nucleophilic attack from the phenol group to afford the desired products. A wide variety of 3-vinyl chromanes could be prepared, including the synthesis of 3-vinyl lapachone from the natural product lapachol. The synthetic utility of this methodology was additionally highlighted by many diversifications performed in the vinyl group of the model product. Moreover, preliminary tests on the enantioselective version of this reaction were performed. Despite the moderate enantioselectivities obtained, these are the first examples of gold(I)-catalyzed enantioselective activation of acetylene gas.

Then, a fully intermolecular gold(I)-catalyzed alkoxyvinylation with acetylene gas was studied in detail where neither the alkene, alkyne nor the nucleophile are covalently linked. After a screening of substrates, N-vinyl amides were found to be suitable substrates for the gold(I)-catalyzed reaction with acetylene gas in the presence of an external alcohol nucleophile. Side oligomerization reactions were observed in many cases, so the possible quantification of the oligomers obtained was investigated by UHPLC-MS in a model reaction.

Finally, the gold(I)-catalyzed biscyclopropanation of 2-alkylated indoles with acetylene gas was explored. The methodology developed constitutes a powerful strategy for the functionalization of indoles, one of the most ubiquitous heterocyclic scaffold in nature and pharmacologically active compounds. In addition, DFT studies were performed to gain insights into the reaction mechanism.