This thesis was split in two parts with the same thematic: multicomponent reactions (MCR). In the first one, we were focused on the development of two novel MCR leading to indole derivatives, an important heterocycle with numerous biological properties. We elaborated two new sequential, rapid and efficient methodologies involving three same partners, an indolic precursor, a terminal alkyne and a Michael acceptor added in predetermined order. This sequence allowed us to obtain two type of heterocycles, cyclopent[b]indoles or pyrrolo[1,2-a]indoles. In the second one, we developed a new diastereoselective total synthesis of trisubstitued tetrahydrofurans-type lignans, known for their abundance in nature and diverse biological activities. This short and efficient synthesis was composed of three key steps: a palladium-catalyzed threecomponents cyclization step, a Krapcho demethoxycarboxylation-elimination procedure and a stereoselective rhodium-catalyzed conjugate addition of an aryl group. This Hayashi-Miyaura reaction has represented the synthetic challenge that we have firstly studied on a model substrate.
