| Abstract
| - Crystal structures of adducts between MeLi and PhLi and a (+)-sparteine surrogate have been determined to reveal a 2:2 MeLi dimer and a 4:2 PhLi ladder structure, each capped by two of the diamine ligands.
- The crystal structures of aggregates betweenMeLi and PhLi and a (+)-sparteine surrogate ((+)-2)have been determined. The MeLi adduct 4 reveals a 2:2dimer, while the PhLi adduct 6 forms a rare example ofa 4:2 ladder structure, each capped by two of the diamineligands. The observation that (+)-2 is equally effectiveas (−)-sparteine in s-BuLi-mediated asymmetric deprotonations, but leading to the opposite sense of stereoselectivity, is explained on the basis of the crystal structuresand a computational study. Moreover, the crystal structure of the 2;2 dimer between MeLi and (−)-sparteinehas been redetermined with advanced accuracy.
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