Lithium tetraalkylcerates

Mioskowski et al. examined the reductive alkylation of simple epoxides by or-ganolithiums in THF in considerable detail, and found that the best yields and stereoselectivities were obtained with secondary and tertiary alkyllithiums (Table 5.2, Entries 1-5) [42]. n-BuLi gave a mixture of olefins (Entry 6), whereas PhLi and MeLi (Entries 7 and 8) gave very poor yields. Similar transformations have been reported with the use of lithium tetraalkylcerate reagents (Entries 9 and 10) [43]. 

Lithium tetraalkylcerates, R,CeLi. These reagents are prepared in situ by reaction of an alkyllithium (4 equiv.) with CeCl3 at -78° — -20°. 

Lithium tetraalkylcerates Regiospecihc synthesis of ethylene derivs. from oxido compds. 

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