Collect. Czech. Chem. Commun. 1997, 62, 1185-1204

Synthesis of N- and B-Substituted Derivatives of closo-Amino-undecahydro-dodecaborate(1-) Anion

Bohumír Grünera, Bernard Bonnetotb and Henri Mongeotb

a Institute of Inorganic Chemistry Academy of Sciences of the Czech Republic, 250 68 Řež near Prague, Czech Republic
b Laboratoire des Multimatériaux et Interfaces UMR no 5615, Université Claude Bernard Lyon I, 43Bd du 11 Novembre 1918, 69622 Villeurbanne Cedex, France


The synthesis of nitrogen and boron substituted derivatives of the 1-amino-closo-dodecaborate anion(1-) 1 is reported. Reasonable yields of the [R2NH-B12H11]- derivatives (R = C6H5CH2, 2-C10H7CH2, n-C16H33, n-C12H25) were obtained via conventional alkylation of 1 in aqueous propan-2-ol, starting from bulky primary alkylhalides. These [R2NH-B12H11]- derivatives were subsequently methylated by dimethyl sulfate under similar conditions. Reaction of 1 with palmitoyl chloride gave under anhydrous conditions the corresponding N-acyl derivative. Reaction of 1 with hydroxymethyl-18-crown-6 tosylate in THF in the presence of NaH led to the novel [(18-crown-6-CH2)2NH-B12H11]- anion, the Cs+ salt of which exhibits unusual solubility properties. A direct cyclization reaction of pentaethylene glycol ditosylate with 1 gave under similar conditions [(15-azacrown)-5-B12H11]-, the first known closo-borate anion with an attached aza-crown ring. These species exhibit potentially interesting complexation efficiency and solubility properties. Selective substitution of the boron cage by a bulky naphthyl substituent was achieved by palladium-mediated cross-coupling reaction between 1 and 1-BrMgC10H7. All derivatives were characterized by high-field 11B, 1H NMR and negative FAB mass spectrometry methods.

Keywords: Boranes; closo-Hydroborate anions; Dodecahydro-closo-dodecaborate(2-) anion; 1-Amino-undecahydro-closo-dodecaborate(1-).