{Ti}/{Ti} Wheel Cluster Substituted Silicotungstate Aggregates.

Two novel Ti-oxo wheel cluster substituted silicotungstates (STs) [HN(CH)]H[TiO(SiWO)]·11HO () and [HN(CH)]H[TiO(SiWO)(SiWO)]·14HO () have been made by hydrothermal reactions. The polyoxoanion of is a ring-shaped trimer where a TiO ({Ti}) wheel cluster is encapsulated by three divacant [SiWO] (SiWO) fragments. However, is built by two divacant SiWO units and two rare trivacant [SiWO] (SiWO) fragments and further installs an unprecedented TiO ({Ti}) double-wheel cluster. To the best of our knowledge, is rare in POM chemistry. Studies on the catalytic oxidation properties reveal that exhibits high catalytic activity toward the oxidation of various sulfides using HO as an oxidant. Furthermore, can be facilely recycled and reused for at least five cycles without obvious loss of catalytic activity.