Imidazolium-urea low transition temperature mixtures for the UHP-promoted oxidation of boron compounds

Different carboxy-functionalized imidazolium salts have been considered as components of low transition temperature mixtures (LTTMs) in combination with urea. Among them, a novel LTTM based on 1-(methoxycarbonyl)methyl-3-methylimidazolium chloride and urea has prepared characterized by differential scanning calorimetry throughout its entire composition range. This employed for the oxidation boron reagents using urea-hydrogen peroxide adduct (UHP) oxidizer, thus avoiding use aqueous H2O2, which is dangerous to handle. metal-free protocol affords corresponding alcohols good quantitative yields up 5 mmol scale without need further purification. The broad range allows reaction be carried out three consecutive times single salt loading offering remarkable sustainability an E-factor 7.9, can reduced 3.2 threefold reuse system.