Solvent-free epoxidation using nitrides and oxinitrides as solid-disperse-phase

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It guessed that the formation of chemical imtermediate which synthesized by solving TaCl_5 in the liquid ammonia was [TaCl(NH_3)_4]Cl_4. The nitride of tantalum was synthesized by heating this chemical intermediate under the condition of depression and the condition of interrupting water as a source of oxygen. The oxynitride of tantalum was obtained heating [TaCl(NH_3)_4]Cl_4 at 780 ℃ using potassium chloride as the flux and adding water of the fixed quantity as a source of oxygen. On the other hand, it was proved that oxides of tantalum was mixed when sodium chloride, sodium bromide, and potassium bromide were used for the flux.That the characteristics of the solid-disperse phase which is suitable for this solvent-free epoxidation were (1) the powder of solid-disperse phase doesn't decompose hydrogen peroxide as the oxidizer, (2) the surface area of solid-disperse phase is about 1m^2/g and the diameter of the powder is about 1μm. Silicon oxide, titanium oxide, aluminum oxide, and calcium fluoride are suitable except for already reported fluorapatite and hydroxyapatite. The solid-disperse phase of the fifth group metal nitride and oxynitride didn't accommodate solvent-free epoxidation because these powders decompose hydrogen peroxide themselves only. Epoxide reaction yield improved when the powder which heat-treatment was given to after titanium oxide soaked in the liquid ammonia was used for solid-disperse phase.