Reactions of oxonium derivatives of [B12H12]2− with amines: Synthesis and structure of novel B12-based ammonium salts and amino acids

The reactions of oxonium derivatives of [B12H12]2− with various amines were studied. A series of novel B12-species with ammonium group on the side chain was synthesized in high yield. A structure of tetrabutylammonium-[2-(2-morpholinium-ethoxy)-ethoxy]-undecahydro-closo-dodecaborate was determined and the existence of intramolecular N–H⋯O–B bond was shown. Using these reactions, novel boronated piperazines and amino acids were prepared.