Group 3 Sc, Y, La Lanthanides and Actinides

A number of reviews with relevant material have appeared. These include reviews on the application of lanthanide reagents in organic synthesis, structural trends of bis(pentaniethylcyclopentadienyl)lanthanide and ytrrium complexes, lanthanide and actinides (literature years 1987-89 and 199(pS), and recent advances in organoactinide chemistry.  

The reaction between UCp4 and BzCl affords either CP3UBZ or CpUBz3.58 The decomposition of Cp ScCH2(c-C5Hg) leads to [Cp Sc( n5,qi-C5Me4CH2)]2 whose AT-ray structure confirms a tucked-in dimeric structure.59 

Treatment of anhydrous YbCls with 2-(dimethylaminoethyl)ferrocenyl lithium in a 1 2 molar ratio affords the o-bonded complex 9. The reaction between [Cp2YbCl]2 and LiFcN [LiFcN = CpFe(C5H3LiCH2NMe2)] results in replacement of a cyclopentadienyl group and formation of 10.66 

The reaction of 1,1-dibromoalk-l-enes with Smia in benzene containing 10% HMPA affords alkynes in reactions probably involving samarium vinyl intermediates. The reactions of diaryl ketones with Sm or Yb metals results in cleavage of the C=0 bonds in reactions possibly proceeding via a l-oxo j,-alkylidene intermediates.  

Some relevant material is contained in reviews on Qi-actinide chemistry, the electronic structure of actinide-containing molecules, ab initio calculatimis on transition metal organometallics/ a survey on the landiankfes and actinides fm the literature years 1984-6, and alkoxo and aryloxo chemistry of scandium, yttrium, and lanthanoids/  

Alkylation of Cp ScCl(OCgH3Bu 2-3,5) with LiMe results in formation of a unreactive complex [Cp ScMe(p-OC6H3Bu 3-5)]2. On the other hand, the corresponding reaction with Cp ScCl(OC5H2Bu 3-2,4,6) affords an extremely reactive species that appears to undergo metallation with an ortho-Bu group/  

The complex [Cp 2Sm(p-H))2 decomposes by an internal metallation process to form complex 7. This reactitm is revm ble and inhibited by hydrogen. In toluene the decomposition reaction is accompanied by formation of the benzyl Cp 2SmBz, isolated as Cp 2Sm(Bz)(THF).72 

The leacdons of the alkynides M(OGni)3 (M = Pr, Sm, Tb) with esters results in additum to the ester u fixm alkoxy complmKes of the type M[OC(GECPhX(W )R ]3 (R R alkyl). Exce ethyne reacts widi various scandium cmnplexes Qp 2 (R - H, alkyl, aryl, allmnyl, alkynyl, amide) to form reacts with excess ethyne to fcmn polyacetylene. The ctxnplex 

Cp 2Sc(OCH) decomposes cleanly to form Cp 2ScOsCScCp2, inobably via o-bmid metadieris involving the Sc-acetylide and terminal C-H bonds of two molecules of Q) 2Sc(OCH).  

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