F. Hanousek

Degradative insertion reactions of nido-7,9-C2B9H–12.Synthesis and properties of 4-thia -6,8-dicarba-arachno-nonborane (10),4,6,8-SC2B6H10

The reaction of 7,9-C2B9H–12(1)with NaNO2and Na2SO3in dilute hydrochloric acid affords 6,8-C2B7H13(2)and the new thiacarbaborane 4,6,8-SC2B6H10(3)the structure of which is proposed on the basis of 1H and 11B n.m.r. spectra.

Behaviour of α-Fe2O3 (hematite), prepared by oxidation precipitation of ferrous sulphate, on heating

The effects of heatingα-Fe2O3 (hematite) prepared by oxidation precipitation of ferrous sulphate, at temperatures up to 700° C were studied. It was found that, in the course of heating, losses of structurally-bound water occured, accompanied by the formation and removal of pores, the lattice constants changed and the optical properties were modified, an effect which is important from the standpoint of the use of hematite as ferric pigment. With increasing annealing temperature, the complementary wavelength was shifted to higher values and the spectral purity of the pigment colour was decreased.

Synthesis of 6-aza-nido-decaborane(12) and its derivatives

The aza-nido-borane 6-NB9H12(1) has been prepared by treatment of the reaction intermediate formed in the reaction of B10H14 and NaNO2 in tetrahydrofuran with concentrated H2SO4; hydrolysis of compound (1) afforded arachno-4-NB8H13(2) and the addition of Lewis bases produced the arachno-9-L-6-NB9H12(3) compounds [L = Me2S (3a), MeCN (3b), and PPh3(3c)].