Activación de aldehídos a,b-insaturados mediante aminocatálisis en procesos enantioselectivos. Cicloadiciones (3+2) y reacciones en cascada Michael/Henry

  1. Fernández Hernández, Naiara
Supervised by:
  1. María Luisa Carrillo Fernández Director
  2. José Luis Vicario Hernando Director

Defence university: Universidad del País Vasco - Euskal Herriko Unibertsitatea

Fecha de defensa: 26 October 2012

  1. Miguel Yus Astiz Chair
  2. Olga García Mancheño Secretary
  3. Gonzalo Blay Llinares Committee member
  4. Maria Esther Lete Exposito Committee member
  5. Anna Roglans Ribas Committee member
  1. Química Orgánica e Inorgánica

Type: Thesis

Teseo: 115445 DIALNET lock_openADDI editor


During the research that it is summarized in the present memory, the activation of enals via iminium ion catalysis in different transformations has been studied. Firstly, a 1,3-dipolar cycloaddition between stable azomethine ylides and a,b-unsaturated aldehydes catalyzed by a chiral imidazolidinone derivative has been optimized. Employing this methodology we have synthesized a large range of densely substituted pyrroloisoquinolines and pyrrolophthalazines with good yields and high values of diastereo- and enantioselectivity. Moreover, a mechanistic study has been carried out based on DFT calculations and experimental data which have allowed us to propose that the (3+2) cycloaddition reaction follows a sequential Michael addition/Mannich cyclization pathway. The formation of the iminium ion as a result of the condensation between the a,b-unsaturated aldehyde and the catalyst plays an essential role, regarding both reactivity and stereoselectivity. On the other hand we have developed a methodology to carry out a cascade Michael/Henry reaction followed by a sequential dehydration. Starting from simple substrates (2-nitromethylacrilates and a,b-unsaturated aldehydes) and employing a prolinol-derivative catalyst a series of quiral nitrocyclohexadienes have been synthesized.