Uranyl alkoxides

U(OR) compounds (R = alkyl or aryl) exist in oxidation states between +3 and 4-6 in addition, there are some uranyl alkoxides. An unusual feature is the number of thermally stable compounds in the otherwise unstable and rare 4-5 state. 

A few uranyl alkoxides have been made, such as golden yellow [U02(0CHPh2)2(thf)2], but more important are the large number of octahedral U(OR)6 compounds that can be made, examples being U(OMe)6, U(OPr )6, U(OBu06, U(OCF2CF3)6, and U(OCH2Bu06 (U-O 2.001-2.002 A). 

Nanocrystals of BaTiO, are obtained by the thermal decomposition of MOeVD reagents (alkoxides such as BaTifOiCCjHis) [OCH(CH,),],) in diphenyl ether containing oleic acid, followed by the oxidation of the product with HjOi. Thermal decomposition of uranyl acetylacetonate in a mixture solution of oleic acid, oieylamine, and octadecene at 423 K gives uranium oxkle nanocrystals. Treatment of metal acetylacetonates under solvothermal conditions produces nanocrystals of metal oxides such as GajOj, ZnO and cubic lujOs. Nearly monodisperse InjOj nanocrystals have been obtained starting with indium acetate, oieylamine and oleic acid. TiOj nanocrystals can be prepared... 

This latter result may be related to the relative acidities of the alcohols and/or stronger binding of the alkoxide ligands to uranyl. 

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