VOTPPCl8 exhibited an axial spectrum which corresponds to the axially compressed dxy1 configuration. VOTPPCl8 was utilised for the selective epoxidation of various olefins in good yields with very high TOF numbers (6566–9650 h−1) in the presence of H2O2 as an oxidant and NaHCO3 as a promoter in a CH3CN/H2O mixture. The oxidoperoxidovanadium(V) species is expected to be the intermediate during the catalytic
我们已经合成了2,3,7,8,12,13,17,18-八
氯-内消旋-
四苯基卟啉对
氧化钒(IV)(VO
TPPCl 8),并通过各种分光镜(UV-Vis,IR和EPR)技术进行了表征,MALDI-TOF质谱和元素分析。CH 3 CN中VO
TPPCl 8的DFT优化结构显示了
卟啉大环的高度非平面鞍形构象。VO
TPPCl 8的循环伏安图与VO
TPP相比,第一环还原电势的阳极位移为500 mV,第一环氧化电势的阳极位移为220 mV,表明
卟啉π系统具有电子缺陷性质,并进一步证明了溶液中大环的非平面构象的存在。此外,如其热分析图中所示,VO
TPPCl 8直到390°C都显示出很高的热稳定性。通过EPR光谱法确认了
金属离子(V IV)的氧化态,并且VO
TPPP1 8表现出与轴向压缩的d xy 1构型相对应的轴向光谱。VO
TPPCl 8用于以高收率和高TOF值(6566-9650 h)对各种烯烃进行选择性环氧化-1)在CH