Transition metal-catalysed [2+2+2] cycloaddition reactions. Methodology and mechanism

The transition-metal catalysed [2+2+2] cycloaddition reaction is a highly efficient synthetic tool that allows six-membered polysubstituted carbo- and heterocyclic derivatives to be obtained in an atom economy process. This doctoral thesis is based on methodological and mechanistic studies of the rh...

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Detalles Bibliográficos
Autor: Parera Briansó, Magda
Tipo de recurso: tesis doctoral
Estado:Versión publicada
Fecha de publicación:2014
País:España
Institución:CBUC, CESCA
Repositorio:TDR. Tesis Doctorales en Red
OAI Identifier:oai:www.tdx.cat:10803/145035
Acceso en línea:http://hdl.handle.net/10803/145035
Access Level:acceso abierto
Palabra clave:Rhodium
Rodi
Rodio
Cycloaddition
Cicloaddició
Cicloadición
Catalysts
Catalitzadors
Catalizadores
ESI-MS
Hemilabile ligands
Chiral
Baylis-Hillman
547
Descripción
Sumario:The transition-metal catalysed [2+2+2] cycloaddition reaction is a highly efficient synthetic tool that allows six-membered polysubstituted carbo- and heterocyclic derivatives to be obtained in an atom economy process. This doctoral thesis is based on methodological and mechanistic studies of the rhodium(I)-catalysed [2+2+2] cycloaddition reaction. In particular, the use of hemilabile S-stereogenic and P-stereogenic ligands for the rhodium-catalysed [2+2+2] cycloaddition is described. The activity of these new catalytic systems is evaluated in the cycloaddition of three alkynes and in the enantioselective cycloaddition of enediynes to obtain chiral cyclohexa-1,3-dienes. Moreover, the participation of Baylis-Hillman adducts as alkene moieties for the partially intramolecular [2+2+2] cycloaddition is described for the synthesis of a set of enantioenriched bicyclic cyclohexadienes featuring a quaternary stereogenic centre. Finally, the mechanistic study of the [2+2+2] cycloaddition of alkynes by electrospray ionization mass spectrometry and DFT calculations is performed.