Continuous stoichiometric silicon nitride fiber was produced by the pyrolysis of perhydropolysilazane. This high-purity silicon nitride fiber is colorless and has high strength, modulus of elasticity, and thermal stability which are properties suitable for reinforcing plastics, metals, glasses, and even ceramics. The structures of three kinds of amorphous silicon nitride fibers (with stoichiometric, Si-excess and 0-excess composition) were investigated by X-ray diffraction followed by calculating the radial distribution functions. Radial distribution functions were calculated from several possible crystal structures and compared with observed radial distribution functions. [

2-Butyne-1,4-diol reacts with aliphatic amines in the presence of a catalytic amount of [RuCl2(PPh3)3] at 150 °C to give N-alkylpyrroles in good yields. 1,4-Butanediol reacts with aromatic or aliphatic amines to give N-substituted pyrrolidines in excellent yields; [RuCl2(PPh3)3] and [RuCl3·nH2O–3PBu3] are the best catalysts for aromatic and aliphatic amines, respectively. The reaction of 2-butene-1,4-diol with alkyl amines gives a 1:1 mixture of N-substituted pyrroles and pyrrolidines in high yield.

Dichlorotris(tripheny1phosphine)ruthenium is highly active as a catalyst for the N-heterocyclisation of 2-aminophenethyl alcohols (2a-d) into indole derivatives in toluene under reflux, and the reactions proceed with spontaneous hydrogen evolution.

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