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

推测在液氨中溶解TaCl_5合成的化学中间体为[TaCl(NH_3)_4]Cl_4。在减压和中断水作为氧气来源的条件下，通过加热这种化学中间体，合成了钽氮化物。以氯化钾为助熔剂，加入一定量的水作为氧源，在780℃下加热[TaCl(NH_3)_4]Cl_4制得钽的氮化氧。另一方面，证明了当使用氯化钠、溴化钠和溴化钾作为助熔剂时，钽的氧化物是混合的。结果表明，适用于无溶剂环氧化的固-分散相的特点是：(1)固-分散相的粉末不分解过氧化氢作为氧化剂；(2)固-分散相的比表面积约为1m^2/g，粉末直径约为1μm。除已报道的氟磷灰石和羟基磷灰石外，适用于氧化硅、氧化钛、氧化铝和氟化钙。第五族金属氮化物和氮氧化物的固分散相不能进行无溶剂环氧化，因为这些粉末只分解过氧化氢本身。将氧化钛在液氨中浸泡后经过热处理的粉末用作固分散相，可提高环氧化物反应收率。

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.