过氧锆杂多配合物的合成、表征及催化性能

Synthesis,Characterization and Catalytic Behavior of Heteropolytungstates Containing Peroxozirconium

合成了 5种钨硅杂多配合物异构体α K6[SiW11ZrO40 ]·xH2 O、α K6[SiW11(ZrO2 ) 2 + O3 9]·xH2 O和 βi K6[SiW11(ZrO2 ) 2 + O3 9]·xH2 O(βi=β1,β2 ,β3 ) ,IR光谱、UV光谱、极谱、I- S2 O2 -3 滴定证明 ,合成的杂多配合物中有ZrO2 基存在 ,183 WNMR光谱证明其阴离子具有Keggin结构。催化实验结果表明 ,合成的化合物对烯烃环氧化反应具有催化活性 ,且过氧杂多配合物的催化活性高于非过氧杂多配合物 ,β异构体的催化活性高于α异构体。

Five heteropoly acid isomers α-K_6·xH_2O, α-K_6[SiW_11(ZrO_2)~2+O_39]·xH_2O and β_i-K_6[SiW_11(ZrO_2)~2+O_39]·xH_2O(β_i=β_1,β_2,β_3) were synthesized and characterized. The IR, UV spectrometry, polarography and chemical titration confirmed the existence of ZrO_2 groups in the complexes. All ~183W NMR spectra revealed the Keggin structure of anions in the compounds. The catalytic epoxidation of maleic acid showed that the catalytic activity of these complexes is higher than those of their corresponding complexes not containing peroxyion. Meanwhile the activity of β isomer is higher than that of α isomer.