A computational study of lithium methoxide mixed aggregates with alkyllithiums

The formation of alkyllithium-lithium methoxide mixed aggregates was modeled with the B3LYP density functional method. In the gas phase there was little tendency to form mixed dimers or trimers. Mixed tetramer formation was more energetically favorable, particularly for tert-butyllithium. THF solvation favored the formation of methyllithium and ethyllithium mixed tetramers, but not those of sec-butyllithium and tert-butyllithium. The potential for resolution of chiral alkyllithiums by mixed aggregate formation with enantiomerically pure lithium alkoxides was examined.