Magnesium and Calcium Bisguanidinates: Catalytic Activity in the Hydroboration of Unsaturated Molecules

The role of ligands in catalytically active metal complexes can be crucial. Herein, we present a study on the synthesis and catalytic behavior of alkaline earth bisguanidinato complexes. The reactivity of trisubstituted guanidines, specifically (iPrHN)2CNR (R=Ph, 2-Ph2PC6H4, 2-MeSC6H4), towards magn...

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Detalles Bibliográficos
Autores: Ginés Gómez, Carlos, Parra Cadenas, Blanca, García Vivó, Daniel, Elorriaga Muñoz, David, Fernández Galán, Rafael, Ramos Alonso, Alberto Emiliano, Carrillo Hermosilla, Fernando
Tipo de recurso: artículo
Fecha de publicación:2025
País:España
Institución:Universidad de Castilla-La Mancha
Repositorio:RUIdeRA. Repositorio Institucional de la UCLM
OAI Identifier:oai:ruidera.uclm.es:10578/42008
Acceso en línea:https://doi.org/10.1002/adsc.202400843
https://hdl.handle.net/10578/42008
Access Level:acceso abierto
Palabra clave:Calcium
Guanidinate
Hydroboration
Magnesium
Descripción
Sumario:The role of ligands in catalytically active metal complexes can be crucial. Herein, we present a study on the synthesis and catalytic behavior of alkaline earth bisguanidinato complexes. The reactivity of trisubstituted guanidines, specifically (iPrHN)2CNR (R=Ph, 2-Ph2PC6H4, 2-MeSC6H4), towards magnesium and calcium alkyls or amides was explored. All the compounds were found to be very active in the hydroboration of acetophenone with pinacolborane. Notably, a calcium-based complex was especially effective in the hydroboration of carbonyl compounds, demonstrating significant chemoselectivity against other reactive functional groups. This complex was also particularly effective in the double hydroboration of nitriles and moderately active in the hydroborative dearomatization of pyridine. Our experimental and DFT studies allow us to propose a mechanism in which the participation of the guanidinato ligands, along with the metal, is key to the activation of both the unsaturated species and borane.