Generation of aminoborane monomers RR′N&z.dbd;BH2 from amine-boronium cations [RR′NH-BH2L]+: metal catalyst-free formation of polyaminoboranes at ambient temperatureElectronic supplementary information (ESI) available: Experimental and characterising data. CCDC 983367 and 983368. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c4cc05145a

Protonation of MeRNH·BH 3 (R = Me or H) with HX (X = B(C 6 F 5 ) 4 , OTf, or Cl), followed by immediate, spontaneous H 2 elimination, yielded the amine-boronium cation salt [MeRNH·BH 2 (OEt 2 )][B(C 6 F 5 ) 4 ] and related polar covalent analogs, MeRNH·BH 2 X (X = OTf or Cl). These species can be deprotonated to conveniently generate reactive aminoborane monomers MeRN&z.dbd;BH 2 which oligomerize or polymerize; in the case of MeNH 2 ·BH 3 , the two step process gave poly( N -methylaminoborane), [MeNH-BH 2 ] n . Amine-boronium cations function as precursors to aminoborane monomers, oligomers and polymers.