From a Bismuth Oxido Diketonate to a Giant Bismuth Oxido Cluster

摘要

Homo- and heterometallic oxido alkoxides,diketonates,and carboxylates have attracted considerable attention as precursors for oxide-based materials.Structurally well defined and properly functionalized metal oxido clusters are also used as nanoscale building blocks in the assembly of organic-inorganic hybrid networks.A number of oxido-bridged units obtained from the hydrolysis of medicinally important bismuth compounds (nitrate,salicylate,citrate) indicate that polyoxidobismuth species play an important role in pharmaceuticals as well.Major pathways for introduction of the oxido groups during cluster formation include microhydrolysis,ether elimination,and oxidation.Several bismuth oxido clusters [Bi_mO_N]~{(3M-2N)+} with surface capping ligands such as hydroxide,alkoxides,aryl oxides,siloxides,carboxylates,and phos-phonates were isolated recently by using solvolytic methods.In addition,a few heterometallic bismuth compounds in which metal atoms are connected through oxido bridges have also been synthesized by similar approaches.