“…Due to that, a large number of classical methodologies have been used for their synthesis, in which the key step is the generation of the six-membered ring, including the aldol reaction, the reductive amination, Mannich reaction, ring closing metathesis, Diels-Alder reaction with imines as dienophiles, aza-Prins cyclization, and intramolecular Michael reaction, among others [110][111][112][113][114][115]. Despite the considerable effort made to date in this field, the development of new methodologies that allow accessing these heterocycles in a stereoselective way, and taking into account environmental considerations as one of the most important points, continue to be of great interest [109,[116][117][118].…”