Derivatives of Boranes, Possible Metal and Boride and Boron Nitride Precursors

Abstract : The synthesis of B10H14 from B5H9 was modified to facilitate large scale production. Reductions of boranes by alkali and lanthanide metals were studied. Depending upon reaction conditions chosen, the anions (BH3)2-, (B2H6)2- , and (B3H8)-were produced. A simple procedure was developed for the preparation of the solvent free salts M(B3H8) (M = K, Rb, Cs). Borohydrides of the divalent lanthanides Yb, Eu were synthesized, structurally characterized, and then converted to lanthanide borides YbB4 and EuB6. New procedures for the preparation of high purity boron nitride as powders and coatings were developed. An essentially instantaneous reaction between B3N3H3C13 and Cs can be initiated at temperatures as low as 135 C to produce very finely divided amorphous boron nitride. The amorphous BN is converted to the turbostratic form by heating it at 1100 C. H3NBH2C1 in solution form can be applied to a surface. Heating to 1100 C in vacuum produces a coating of turbostratic BN.