Lanthanum organometallic compounds

In this article the term organometallic compound includes alkyl and aryl derivatives of the rare earths—the transition metals of group III, scandium, yttrium, lanthanum and the lanthanides cerium to liitetium with covalent metal-to-carbon a-bonds, as well as the so-called 77-complexes with more than monohapto metal-to-carbon bonds, for example cyclopentadienyl and olefin complexes, metal acetylides, but not carbonyls, cyanides and isocyanide complexes. Derivatives of scandium, yttrium and lanthanum are included and discussed together with the compounds of the lanthanides, because of many similarities in the synthesis and the chemistry of these organometallic derivatives of the rare earths. 

The first indications of the existence of organometallic compounds of the lanthanoides was furnished in the observation that methyl radicals do react with lanthanum metal (l). The publication of the successful syntheses of Sc(C2Hs)3 and Y(C2H5)3 (2), the first supposed alkyl derivatives of the rare earth metals, however, proved to be wrong (3). Also, all attempts to prepare the first phenyl derivatives of lanthanum, carried out by Gilman and coworkers in connection with the separation of... 

Barium oxide, barium salicylate and/or other organobarium salts 2) Organometallic salts of lanthanum, hafnium and tantalum and their oxides Replacements for lead and copper compounds currently employed for ballistic modification. Particularly attractive due to production of considerably less smoke during combustion of propellants [245]. 

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