Samarium chlorides

Aliphatic and aromatic carboxylic esters are also directly converted, in one step, to oxazolines using amino alcohols. As expected, harsh conditions are required for this transformation. Typically, the reaction is performed in refluxing xylene in the presence of catalytic quantities of a Lewis acid such as dibromo- " or dichloro-dimethylstannane. More recently, lanthanide chloride and samarium chloride have also been reported as useful catalysts for this one-pot transformation in refluxing toluene. Representative examples are shown in Table 8.2 (Scheme 8.2). ... 

Anhydrous samarium chloride when mixed with liquid ammonia in a sealed tube is converted into a bulky white powder having the composition [Sm(NH3)l L.5]Cl3. If progressively heated it loses ammonia at eight different temperatures, indicating the formation of derivatives of composition [Sm(NH3)9.5]Cl3, [Sm(NH,)g] Cl [Sm(NH3)5]Cl3, [Sm(NH3)4]Cls, [Sm(NH3)3]Cl3, [Sm(NH,)a]a [Sm(NH3)]Cl3, respectively.2... 

Ammino-derivatives of Rare Earth Salts—Derivatives of Neodymium Chloride and Samarium Chloride—Pyridine Derivatives of Rare Earth Chlorides. 

The anionic copper complexes of N1,N4-Ai5(salicylidene)isosemicarbazidate ion (L) are used in the reactions above. As a result of their interaction with lanthanum and samarium chlorides in chloroform-methanol suspension, the heteronuclear Lu,La-or Cu,Sm-complexes are formed [449]. 

Carrier free in the form of yttrium chloride was obtained from Perkin-Elmer LAS (Belgium). Carrier free In in the form of indium chloride and 2 1 in the form of sodium iodide were obtained from Amersham (UK). Samarium-153 in the form of samarium chloride with a specific activity of 10-15 GBq/mg was obtained from the Nuclear Research Institute Rez pic (Czech Republic). 

Watson (1980), Watson et al. (1981) and TiUey and Andersen (1981b) prepared bis(pentamethylcyclopentadienyl) ytterbium, lutetium, neodymium and samarium chlorides and iodides. Some physical data of these compounds together with those of the other complexes with substituted cyclopentadienyl ligands are given in table 8. The following synthetic methods have been used ytterbium metal is oxidized by CjMejI in the presence of Lil in ether to give, via CjMejYbl, the complexes shown in eq. (20). In the absence of Lil, only dimeric pentamethylcyclopentadiene was isolated. 

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