CAJ | 학술논문

六缺位Dawson型钨磷酸盐K12 H2 P2 W12 O48·24H2 O在NaAc-HAc缓冲溶液中发生自聚，形成了Na21[Na12 H7 P8 W48 O184]·70H2 O（简写为Na-P8 W48）轮型化合物．利用单晶X射线衍射、IR和XRD对Na-P8 W48进行了表征，在该化合物的轮内12个活性位均被Na＋占据．以环己醇氧化合成环己酮为模型反应，探讨了｛P8 W48｝的氧化催化性能．考察了不同物料比、催化剂用量、反应时间、温度及催化剂的溶解性对反应的影响．结果表明，当环己醇/H2 O2的摩尔比为1∶2．2，环己醇/｛P8 W48｝（以W计）的摩尔比为200∶1，80℃反应3 h ，环己酮产率最高，在均相体系时产率可达93％，是环己醇氧化合成环己酮的优良催化剂．
륙결위Dawson형오린산염K12 H2 P2 W12 O48·24H2 O재NaAc-HAc완충용액중발생자취，형성료Na21[Na12 H7 P8 W48 O184]·70H2 O（간사위Na-P8 W48）륜형화합물．이용단정X사선연사、IR화XRD대Na-P8 W48진행료표정，재해화합물적륜내12개활성위균피Na＋점거．이배기순양화합성배기동위모형반응，탐토료｛P8 W48｝적양화최화성능．고찰료불동물료비、최화제용량、반응시간、온도급최화제적용해성대반응적영향．결과표명，당배기순/H2 O2적마이비위1∶2．2，배기순/｛P8 W48｝（이W계）적마이비위200∶1，80℃반응3 h ，배기동산솔최고，재균상체계시산솔가체93％，시배기순양화합성배기동적우량최화제．
A Wheel-type tungstophosphate Na21 [Na12 H7 P8 W48 O184 ] · 70H2 O (Na-P8 W48 ) ,with twelve active sites occupied by Na+ ,was synthesized in NaAc-HAc buffer solution by self-assembly of the hexavacant Dawson-type tungstophosphate K12 H2 P2 W12 O48 · 24H2 O .It was characterized by single crystal Xray diffrac-tion ,IR and XRD analysis .Using the oxidation of cyclohexanol to cyclohexanone as a model reaction ,the cat-alytic activity of {P8 W48}was evaluated ,and the reaction conditions ,such as the molar ratio of starting mate-rials ,the amount of catalyst ,the reaction time ,the reaction temperature ,and the solubility of catalyst ,were systemically explored .The results show that the optimum conditions for the oxidation of cyclohexanol were :the molar ratio of cyclohexanol/H2 O2 was 1∶2 .2 ,the molar ratio of cyclohexanol/{P8 W48} (based on W ) was 200∶1 ,and the reaction time was 3 h .Furthermore ,the yield of the cyclohexanone can reached 93% u-sing {P8 W48}as a homogenous catalyst ,the wheel-type POMs were excellent catalysts for the oxidation of cyclohexanol to cyclohexanone .