Ammonia-mediated, large-scale synthesis of ammonia borane

Abstract

A simple, large-scale synthesis of ammonia borane from NaBH₄ and (NH₄)₂SO₄ at 0 °C–rt in THF containing 5% NH₃ is described. The presence of ammonia is critical for the reaction to proceed and allows the reaction at high concentrations and ambient temperature without the need for anhydrous solvent or inert atmosphere.