Addition of n-butyllithium to an aldimine: role of chelation, aggregation, and cooperative solvation.
Rate studies of the addition of n-BuLi in the presence of TMEDA to potentially chelating aldimines are consistent with a combination of monomer- and dimer-based mechanisms. Using mixtures of TMEDA and Et2O reveals cooperative solvation in which both Et2O and TMEDA coordinate to lithium at the monomer- and dimer-based transition structures. The four discrete mechanisms are affiliated with markedly different stereochemistries of the 1,2-addition.
Qu
Bo
B
Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, NY 14853-1301, USA.
Collum
David B
DB