The Interaction of Benzyl Alcohol with Trimethoxyboroxine : Amine Adducts of Triarylboroxines as Model Compounds

Abstract

The interaction of benzyl alcohol with trimethoxyboroxine has been investigated by hydrogen-1 and carbon-13 NMR and IR spectroscopy. These techniques indicate formation of a weak Lewis acid/base adduct, additionally stabilized by a hydrogen-bonding interaction, which undergoes rapid ligand exchange at room temperature. The system has been modelled by the synthesis and characterization of a series of amine-triarylboroxine adducts. These adducts rapidly undergo ligand dissociation-recombination in solution with ΔG⁺ of ca. 40-50 kJ/mol.

Keywords::

• Boroxines
• Lewis base/acid adducts
• Ligand exchange