Details

Autor(en) / Beteiligte

• Sepúlveda, Francisco
• Carrión, M. Carmen
• Phillips, Andrew D.
• Jalón, Félix A.
• Dyson, Paul J.
• Manzano, Blanca R.

Titel

Base‐Free Transfer Hydrogenation with an Ionic‐Liquid‐Supported Ruthenium η6‐Arene Bis(pyrazolyl)methane Catalyst

Ist Teil von

• European journal of inorganic chemistry, 2017-01, Vol.2017 (3), p.630-638

Erscheinungsjahr

2017

Link zum Volltext

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Ruthenium complexes of the type [RuCl(η6‐arene)(NN)]X (X = BF4 or BPh4) featuring an η6‐arene ligand modified with an imidazolium ring and incorporating the bis(azo) chelating (NN) ligands 2‐hydroxyphenylbis(3,5‐dimethylpyrazol‐1‐yl)methane or 2‐nitrophenylbis(3,5‐dimethylpyrazol‐1‐yl)methane are reported. The catalytic activities of the complexes were evaluated in the transfer hydrogenation of benzaldehyde to benzyl alcohol with iPrOH as the hydrogen donor in the absence of a base and under biphasic conditions; one of the two phases was iPrOH, and the other was an ionic liquid. The catalysts featuring the imidazolium‐modified η6‐arene could be recycled and reused with only a minor decrease in substrate conversion after multiple reaction cycles. The reaction rate was strongly influenced by the type of ionic liquid employed in the biphasic system. The transfer hydrogenation of benzaldehyde with iPrOH under base‐free, biphasic conditions with ionic liquids (ILs) is reported. The precatalysts are ruthenium bis(pyrazolyl)methane derivatives with an η6‐p‐cymene ligand modified with an imidazolium tag that allows a high level of recycling. The highest activities are obtained with non‐coordinating ILs.