Metal alkoxides trimetallic

Building on earlier synthetic reports in this area, the Zr/Al bimetallic derivatives ZrA X OPP) 10[ZrAlXaCOlVfdaaVOIIh ( =1, 2 X = C1, Br, MeCOCHCOMe),393 and ZrAl(OPr )7 L (n= 1, 2 L = RCOCHCOMe (R = Me, Ph), MeCOCH C02Me (R = Me, Et))394 were prepared. However, it was not until the X-ray crystallographic study of the related Hf complex Al2nf(OPr )io (86) that the nature of these trimetallics was well understood.395 This compound was prepared via prolonged refluxing of the respective metal alkoxides. 

An important development of this method has recently been carried out by Mehrotra and Veith. The reaction with the excess of halide was found to provide bimetallic alkoxide halides. Their interaction with the alkoxometallate of the third metal provided access to trimetallic alkoxides ... 

The dimers [CpY(p.-0 Bu)(0 Bu)]2 and Cp2Y(p,-0 Bu)2Y(0 Bu)Cp have been synthesized in the context of reactivity studies of the trimetallic yttrium alkoxides Y3(0 Bu)7Cl2-(THF)2 with alkali metal cyclopentadienyl reagents (Evans et al. 1993a) and their X-ray structure determined. 

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